Get a belt holster and a way to carry 2-3 mags. Eyes and ears. 200 rounds of ammo. Show up and say you're new.... Victory.
Really there's not much you need to do. You can shoot that gun in the carry optics division which will let you load your mags to capacity. Max round count on a stage (if you don't miss) is 32 rounds so with 46 rounds you should have plenty. USPSA is a very friendly sport and your squad mates will help you out if you tell them you're new.
Been my favorite sport for going on 10 years now. Enjoy!