The "Heavy Duty" snaps I used were purchased at Home Depot.If you've never installed a snap before it's real easy.As far as reference from mine goes,you really don't need any with doing it this way.
I used 8 snaps on the R/L chest peices each,10 on the bottom,3 on the diamond,2 on each shoulder,2 on each side of the collar armor-back,2 on each knee,2 on each side of the cod/butt plate,4 on the inside of the cod to corresponding snaps (M/F) on the jumpsuit,one on the front of the cod for the "thong",and one on the butt plate to attach it front and back.
There is no one pattern to use just whatever you think will hold best,.....more is better of course,but too many makes it harder to put on.I made custom mounts out of thin gauge welding aluminum (also from Home Depot)for my snaps to put on my armor then JB Welded them on.I then used the setting tool to put the corresponding snaps on the jumpsuit.I put a dab of white paint on the armor snaps after they had all cured,and then pressed against the vest to mark EXACTLY where the snaps were to go.Then I punched through the vest with a scratch awl,and into the snap back,then hammered it on.
This sounds complicated I'm sure,but it's more methodical,and repetitive once you start it.I've done my Trooper armor this way,and now my Fett.Next I'll do my Sandtrooper.It becomes self explanatory once you start,and you'll find your own way to make it work for you.The hardest part is jumping in,and just doing it,.......oh,and punching holes in a vest that you know can't be replaced
Steve