If you have purchased unstrapped armor and want to add straps and buckles to it, it is a good beginner project. Here are a few pictures and a quick rundown of how it's done.
Cut your strap out from the leather. Nip the corners, or if you have a strap-end cutter, use that for a nice, curved edge. Next, punch a hole near the end of the strap for the buckle keeper to pass through. I prefer a rotary punch, such as the one pictured below. Next, cut a hole for the strap using a strap-end punch, such as this silver one. Basic strap and one with the punch and slit cut:
Next, grab your buckle and place the keeper through the hole:
Be sure the keeper, if angled, is facing the right direction. Here's a view from a different angle:
Next, punch another hole in the strap so that you can pass a rivet through it. Grab a rivet and washer, placing the rivet through the strap first. Next, place the washer on the "inside" part of the strap. In this picture, the rivet is longer than it should be; trim it down if necessary.
Trimmed down. NOTE: I did leave it a bit too long (first time riveted something in ~10 years and basically forgot how):
Place it over your anvil, rivet set, or other hard metal surface:
Peen the rivet down, working in a circle, starting on the outside. The idea isn't to smash it into submission, but to try to gently form a "mushroom" out of the exposed top area, to hold the washer in place and keep the rivet from coming out. Think of it as trying to turn "l" into "T" and have the top "lip" keep things in place. Now, our buckle side is done, so we just need a strap. Cut a strap to length:
Punch holes for the buckle keeper:
I decided to re-use a rivet hole where the splints were already riveted to the leather. Here's a slightly better set rivet, in the center of the picture, holding on the strap:
Straps and buckles attached:
It works. Huzzah!
TOOLS:Strap cutter by Craftool, available here on Amazon:
http://www.amazon.com/Craftool-%C2%AE-Strip-Strap-Cutter/dp/B0036UU0AG/ref=sr_1_cc_1?s=aps&ie=UTF8&qid=1330494065&sr=1-1-catcorrRotary punch from Home Depot. They're available in a lot of places, such as Brettuns Village (
http://www.brettunsvillage.com/leather/tools/tools.html).
Leather is from Brettuns Village Leather (
http://www.brettunsvillage.com/leather/)
Strap slit cutter from somewhere online (can't remember)
Buckles from Tandy Leather
NOTE: I've bought from Brettun's Village multiple times and highly recommend them. They carry leather, leather tools, plastic and rawhide mallets ... lots of stuff for working with leather. I also recommend Tandy Leather; I've only bought from them once, but they have a wide selection of items too. If you can't find it at Brettun's, and you can't find it at Tandy, it might not exist - though both stores have quite a bit of overlap in items, each has some of it's own unique items too, so check both out.