Quite a broad question. Agencies and publicists that are experienced have learnt many things over the years, which will all play part of best practice. As a staring point, would suggest you think about the following:

- Ensure your pitch is concise and to the point. Lead with what is most newsworthy to readers of the publication you are targeting
- Be harsh. Consider if what you are sending them really news?
- Rearsearch the journalist and tailor pitch to reference articles they have written or areas they have an interest in
- Go to the right person. Don't sent an irrelevant story to the journalist. Make sure they actually write about what you are sending them
- Be prepared. Have facts and information ready
- Use the phone. Imagine how many emails they get each day! You're far better pitching on the phone, and talking over the news and then following up with tailored into based on their feedback

If you get the approach wrong then your pitch is going to be sent to the junk folder and you simply won't get a reply or answer.

Hope that's not too blunt! Hope it helps. Thanks.

The biggest fundamental mistake could be not seeing it as a PR initiative and thus it should revolve around what you do for your customers. How can your customers benefit from you and your PR efforts. Brag about them not you... How the marry gave you the opportunity... How customers trusted a feature, etc

As a former journalist and 26-year public relations veteran I have found that the first criterion is whether you are ready for "prime time." Many startups operate under the mistaken notion that they have something newsworthy for a journalist to cover. For example, they issue a press release about a new website or a non-key hire. Before reaching out to journalists, have your funding, strategic plans, market research, production and personnel in place, then be ready to explain why your startup is "news" and should be covered. I'd be happy to expand in this in a call.

Forgetting the why and objective for talking to press in the first place.

One of the biggest mistakes is over-promising. Everything on the internet should be taken as a matter of public record. So when startups make claims they cannot backup, any interest they created will turn into "badwill" with the public.