You:
.attend city council meetings.
.go to party events.
.campaign for incumbents.
.testify at hearings.
.run for city council and work your way up to state or fed.
.get your law degree.
.make the news and get free press/air time.
.write letters to the editor or perhaps have a regular column in well circulated local newspapers / publications.
.get your name out there in a good way – it is all about name recognition. if you want to be a public figure get out in the public.
.pick up an issue that you are passionate about and make change happen (involves petitioning people currently in office to introduce legislation, creating a following to submit testimony on this legislation, and getting the votes to pass it).
.get good at fundraising.
.network.