Do interesting research.

Have a blog. Write about your research, comment on common misunderstandings and stuff you find interesting. Link to your blog from your university page. (Here is an excellent example)

When journalists search for information, they will see that you are the explaing kind, and they will see what your topics are.

Write summaries of your research (on your blog or elsewhere).

At IFN, working paper summaries in Swedish are mandated (example). I hate writing them, but having written them is wonderful.

Occasionally reply when others get it wrong (here's an excellent example).

Yes, you should bother. It is a virtue, and it is part of your job-description.

When journalists call or email, answer, reply or get back to them.

Be prepared to explain stuff about research questions, uncertainty, normative vs descriptive, causation vs causality. Yes, you should bother. It is a virtue, and it is part of your job-description.

If you don't know or are not sure: Give pointers to other researchers who know more, when you know these exist. Or ask for time to check the literature for 15 minutes and then get back to the journalist.

You are much more productive in searching and validating research. Journalists who are not willing to give you 15 minutes to find a serious answer, are not serious.

Ask to check the text and how your are quoted before publications (again, if they won't let you, they are not serious) OR just accept that you will sometimes be misrepresented and let it go (easier later in your career)

If it is radio/TV, remember that time flies and you will only be able to cover half of the most basic stuff. At best.

If you are misrepresented, or if your position was too nuanced to be newsworthy, see 2.

Remember that there is no reason to add a tenth point to your list just because 10 is a nice and even number. Content is what matters.