Set your zero perfectly, hang a chalkline from the top of your target and snap a vertical line.
You'll shoot at a bullseye at the bottom, shoot your zero then dial up your scope in 5 or 10 moa increments.
I like to make a line at 10, 15, 20, 25,and 30 minutes.
look up the exact measurements an moa is not a true inch at 100 yards.
This is a very important test, my vx5 failed miserably