In Nevada, the process to become a national delegate begins with getting elected as a delegate at the precinct caucuses.

All Delegates and alternate delegates elected at the precinct caucus will meet in March at their county convention. The county convention will then elect delegates and alternates to represent them at the State Convention in April. And it’s at the State Convention where the delegates and alternates get elected to the Republican National Convention in September.

(Source: http://www.nvgopcaucus.com/questions-and-answers)