First Cycle Info?

hey guys! im new on here, my name is Ricardo im 23 years old. ive been working out for 4+ years now, im 6ft at 200lbs, an at 16% body fat. I decided to start my very first cycle. i know what comes with the game and im ready for it. anyways i was just curios, im going to do at 12week cycle of Test E. The only part that confuses me just a bit, ive have done my research of pct an all, but im still confused a little about it. like do i start my pct right after my last injection of test e? or do i need to be taking some during my cycle every other day? can someone please help me understand it just a bit better? if anyone could id really appreciate it thanks guys!