Umm, if you're going to shoot a DCM match, you'll be required to shoot a service rifle. M1 Garand, M14, or M-16 or civilian equivalants. Most clubs have quite a few "club guns" that you can use. If it's an NRA Highpower course, then you can shoot whtever you want pretty much, as long as it has open sights, because you'll be shooting as a Match Rifle.
Swampy said this:
1907 leather or M1 cotton web sling.
The cotton sling, although I don't like it, is probably more simple for the person who isn't really interested in learning the finer points of the leather sling. However, if you reall want to get serious, don't buy a leather "match" sling from joe blow, buy a Turner or one from Leslie Tam.
A padded leather glove or mit to protect your left hand from the
slings pressure.
For your first couple of times, a old winter glove will work for this.
An old piece of carpet to use for a mat. Two ft x 7 ft. is about right. A couple of throw rugs will work in a pinch.
I'd go wider...of course, I shoot "across my position" a little, so I take up more room.
Spotting scope, for spotting your shots.
You can use binocs if you're not getting serious. You'll just be looking for the big spotters and score disks anyway (assuming that you'll be shooting at full distance)
Practice the three positions beforehand
Amen! If you have the time and you can afford it (some can't) buy Jim Owen's books, "Sight Alignment, Trigger Controll, and the Big Lie," and "Leather Sling Use and Shooting Positions." His other books are good too, but these two are REALLY good for the beginner.
Just remembered, you don't have to shoot a DCM or NRA Highpower match to qualify for the M1...you just have to "shoot 50 rounds for score at a DCM affiliated club" IOW, you could shoot a water pistol and score your 50 hits at the club, and qualify. However, is it in the spirit of the CMP?