If the program is still run as it was 25 years ago you need to pass a background check with the local LEO, participate in a military type rifle match, then send your target, fee, etc in with an application.
Yeah, there is a list of hoops that have to be jumped through. It’s not as easy as it should be. I better get up to date now so I will be ready when the time comes.
The Participation in Competition is waived for Ex-Military.