Successful SEO depends on two things: The amount of time the SEO has to invest (which often correlates to your budget) and the skills of the SEO doing the work. Without those two things, it's difficult to answer question number one.

SEO, and digital marketing, in general, require a lot of skillsets that most people don't have. They have some, but not all. They should, however, be letting you know what activities they are doing and explaining why they are important and what the results should be.

As for the second question, there is a lot to do and it's a matter of prioritizing. Ten SEOs will tackle the same project ten different ways, but that doesn't necessarily make any of them wrong. A great resource you can use to understand what an SEO can/should be doing is webmarketingchecklist.com (disclosure: I wrote it.) This will at least give you a place to start an intelligent conversation and set priorities.

As for milestones, you need to determine what your goals are. Are you going for sales, leads, traffic or conversions? What are you getting now and what do you hope to achieve. Then have a conversation with your SEO to determine if your expectations are realistic with the time they have to invest.

Make sure the SEO guy gives you reports each month showing progress in the rankings

Specifics milestone points will depend upon budget, level of competition, and starting point. But if the budget is being allocated properly, you should expect the following. If you want an outside person to review things and such, let me know (donnie@inboundable.com)
- published content about your target keywords
- more websites linking to that published content
- more website visitors from those links
- more sales from those visitors
- from referrals from those sales

First and foremost, you need to know what the SEO consultant is working on each month. Ask for specifics on tasks and closure of any known deliverables.

Second, I would also ask him to send you reports or generate your own reports. Here are some of my favorites:

Google Analytics

Visitors
Page Views
Bounce Rates
Pages Per Visit
New vs. Returning Visitors
Traffic by Channel
Traffic by Source
Traffic by Social Media
Traffic by Referrers
Top Search Queries
Top Landing Pages
Most Popular Pages
Top Exit Pages
Conversions by Goal
Conversions by Medium
Revenue by Channel

SEMrush

Domain Overview
Positions with Changes
Top Pages
Competitors
Site Audit
Link Audit

SpyFu

Domain Overview
SEO Overview
Page 1 Keywords
Almost There Keywords
Pages 2 to 5 Keywords

A lot of the SEO jargon is not going to make sense to most business owners (and will only make sense to your internal marketing team, if you have one in place).

That said, you can judge how well your SEO consultant is doing by three metrics:

1) Are you getting more traffic?
2) Is that increased traffic resulting in more sales or other goals?
3) Are you moving up in the rankings?

The proof is in the pudding, and if these three things aren't happening, the rest is inconsequential.

But, the way that your SEO consultant goes about getting results DOES matter. You want to be sure that the steps they are taking will have long-lasting effects that don't disappear the next time Google cracks down on "black hat" SEO techniques that seek to manipulate the rules.

The two things your SEO expert will be doing to help your rankings improve will be On Page Factors and Off Page Factors.

On Page Factors will be easy to spot. They may add or improve content on your site, change the layout of your pages, tweak the design, change the URL structure, or organize your content better.

Off Page Factors mostly comes down to link building. Ideally, your SEO consultant is building links in places where your buyers already hang out. In other words, you would want these links, even if search engines didn't exist, because they would drive qualified leads.

What you want to avoid is hiring a black hat SEO who builds back links to your site on Private Blog Networks (Google this term) or in other shady locations. You may be happy in the short-term if your ranking improve, but black hat link building can come back to bite you in the a$$ and even earn you a Google penalty.

To sum up, you'll know if your SEO expert is doing a good job if your phone starts ringing more often and you start getting more online orders.

Be aware that Bing seems to reflect changes more quickly than Google does. For whatever reason, Google seems to implement changes to rankings a bit more slowly than Bing.

A reasonable time frame to see results in most categories is about six months, Depending on how competitive your vertical is, it may be less or more time than this to get the exact results you are looking for, but six months should be more than enough time to determine whether you are seeing progress or not.

Hope that helps shed some light on your question.

Be it a SEO guy or be it SEO firm, if it is problematic it will show the following signs:
1. They have nothing to show.
Your SEO agency should have something to show you. I am not talking about results or a rise in rankings. Instead, the agency should be able to show you the actual SEO practices they are doing. Two, three, or even four months into a contract might be too early for significant SEO results, so do not sweat it if you are not seeing the top results you were hoping for. However, your SEO agency should be doing something with the money that you give them. You have a right to ask for deliverables. Here are some of the things that an SEO agency might be able to provide in the first few weeks or months of a contract:
a) An SEO audit of your site
b) An analysis of your site’s link profile
c) Optimized content on your site
d) Articles with links to your site that are being or have been published on other sites
This is just a sampling. Whatever the case, you should make sure that they are doing something and have proof of it.
2. They do not ask you for anything.
An SEO agency that is doing good stuff is going to need your help. You are the site owner, so they might ask you for the following:
a) Editor or admin access to your CMS
b) View or admin access to Google Analytics
c) Access to Google Webmaster Tools
d) Access to social accounts
e) A list of target keywords
f) Past audits/penalties/work
If they do not ask for anything, it could be that they are merely adding linkbacks from their vast network of spammy sites. They do not need access, and there is a chance they are performing potentially harmful actions.
3. They have no suggestions for improvements.
If an SEO agency is not asking you or telling you to do certain things, it is a sign that they are up to something suspicious either that or doing nothing at all. Disreputable SEOs often just point a bunch of linkbacks to your site. They are hoping that their low efforts will yield high results. They are not interested in interfacing with you, their client. Instead, they just want to give you something that will make you think that you are getting a benefit.
4. They cannot share their techniques.
If you are curious as to what your SEO is doing, and you should be — ask them.
“So, what it is exactly that you guys are doing?”
Any of these responses are glaring scam signals:
a) “As an SEO firm, our efforts on your behalf must remain confidential.”
b) “Due to the nature of the industry, we’re not permitted to disclose our practices.”
c) “Well, we do a variety of things, but it involves basically optimizing your site for search engines.”
d) “Oh, tons of things. It would take me too long to explain.”
e) “I’m not sure exactly, but I’ll get back with you.”
If you get an answer like that, I recommend firing the agency as fast as you can. True SEO involves white hat practices that are accepted as legitimate and are proven to get results. If your agency is doing those things, they should be able to explain them.
5. You get a manual penalty.
A manual penalty is one of the worst things that can happen to your site. You will know if you receive a manual penalty if you get a GWT notification or an email message. If you receive a manual penalty one or two months after commencing work with an SEO agency, you have a right to be suspicious. Obviously, you do not want to fire them right away. Just because you got a manual penalty does not mean it is their fault. But it might be. You need to do some careful thinking and close questioning to find out exactly why your site was penalized and what to do about it.
6. Your rankings drop.
Rankings drop for a variety for a variety of reasons. I recommend that you keep an eye on your rankings (but not obsess over it). If you notice that your rankings are steadily declining, then your SEO might be performing actions that are getting your site algorithmically penalized. You need to find out what the agency is doing. If it sounds, looks, feels, or smells suspicious, get them get them to stop.
7. Your traffic drops.
A sudden traffic drop, like a rank loss, could be the sign of an algorithmic penalty. This is a bad thing. It may or may not be your SEO’s fault. The cautious response is to be suspicious and start asking questions. First, find out if there have been any algorithm changes which could have coincided with the traffic decline. Second, determine exactly what changes were made to your site in the days and weeks leading up to the decline. Finally, get an accurate picture of what offsite actions were taken by your SEO agency.
8. You start ranking for the wrong keywords.
You should already know what your target keywords are. In addition, you should have an idea based on Google Analytics, how your longtail keywords are driving traffic and/or ranking in the SERPs. To determine analytics on this, navigate to Acquisition → Keywords → Organic. If your organic keywords change significantly, beware. If you begin gaining traffic from the wrong keywords, it is happening for a reason. Or, if you stop ranking for previously high-ranking keywords, this is also problematic. Your goal in growing your traffic is to earn targeted traffic. If, for some reason, the traffic comes from arbitrary or suspicious queries, then it could a sign of indiscriminate and careless work by an SEO.
9. You see an uptick in suspicious linkbacks on your link profile.
One of the metrics that you need to watch is your link profile. Your link profile is like a sign that you wave to Google telling them, “Here’s how to rank me!” If your link profile gets messed up, your site is in trouble. How does a link profile get messed up? It gets messed up when your site receives too many questionable linkbacks from spammy or suspicious sites.
10. You see optimized anchor text from linkbacks.
“Optimized anchors” are a major no-no in SEO today. Google’s Penguin update way back in 2012 penalized 3.1% of all sites that showed signs of anchor optimization, and more recent updates have kept with the trend. Optimized anchors consist of an anchor text made up of your keywords. For example, let us say your site is “www.cheapelectricguitarsonline.com.” You are trying to rank for “cheap electric guitars online.” You gain a backlink, and the keyword is “cheap electric guitars online.” That is a textbook example of anchor optimization. If you find, based on research into your link profile, that you are gaining a substantial amount of such optimized links, then it could be the devious work of your duplicitous SEO.

But if you do find the following signs then your agency is surely helping you out:
1. They have deliverables.
A quality SEO firm is going to show you what they are doing. They may not be able to show you first-page results, but they do give you evidence of things that they have done.
For example, they may show you the following:
a) Actual sites that have real do follow backlinks to your site
b) An audit of your site, homepage, content, or link profile, that includes action points
c) New content for your pages, or changes to your existing content
d) A weekly or monthly report, displaying work they have done and how your site ranks
SEO agencies cannot wave the magic wand to improve rankings, but they can do things. If they show you exactly what they are doing, that is a good sign.
2. They have recommendations for improvement.
No SEO can help you unless you are helping them help you. If they recommend that you do certain things, this tells you that the agency wants to work with you in a partner relationship. If you comply with their requests, you will most likely see the kind of results that you are hoping for. Here are a few of the things that quality SEO agencies may recommend:
a) Start social channels — Facebook, Twitter, YouTube, Google+, LinkedIn, etc.
b) Integrate social channels with home page
c) Launch a content marketing plan
d) Start a blog
e) Add content to your homepage
f) Integrate internal linking into your existing content
g) Optimize all site content
h) Add alt tags to images
i) Change your robots.txt to allow crawling on other portions of the site
j) Create a sitemap.xml
k) Improve site speed
l) Add WP plugins like Super Cache or Yoast to enhance SEO
m) Perform a link profile audit
n) Disavow spammy links
When the agency makes such recommendations, they are not necessarily trying to upsell you or scam you. Sure, the “extra services” audits, content, etc. might cost. But this is not throwaway money on your part. These SEO services are intended to help you.
3. Your ranking improves.
Everyone loves to talk about rank, and everyone loves to see rank improvements. If your SEO agency is giving you better rank, then you are probably in good hands.
Here are signs of legitimate and trustworthy rank improvement:
a) Your site is ranking for your target keywords
b) Your site is ranking on the first page of Google
c) Your site is ranking for a variety of longtail keywords
d) Your ranking stays consistent. Shifting a few positions up and down on a weekly basis is normal. Dropping several positions day after day for several days at a time is not good.
4. Your traffic goes down, but your revenue goes up.
In some cases, you may work with an SEO agency, and subsequently see your traffic drop. Is this cause for concern? Yes, but only if your revenue goes down. It is possible that your traffic drops, but your revenue increases. Understand this: Your goal is targeted traffic, not just lots of traffic. If you receive less traffic, but it is good traffic, then you will improve your revenue.
How so? “Good traffic” consists of traffic that comes from
1) the right longtail keywords,
2) the right audience.
This kind of traffic is more likely to convert on your site. The result? You get more conversions and revenue from fewer visitors.
Besides if you do have any questions give me a call: https://clarity.fm/joy-brotonath

A good SEO expert will get you seeing results in a couple of months. More importantly, you should get a regular report as to what has been done, as well as what strategies are in play.

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