It's a skill... It's hard to learn it from watching a video, but here's the best one I could find:
http://www.youtube.com/watch?v=fSy-344m-XwLay your uniform out flat. Get the wrinkles out.
Rolling sleeves depends on your uniform size and your arms.
Your first fold will be the cuff length, but a fake uniform might not have the right cuff length for a USMC style rolled sleeve. The first fold should be 3 fingers thick, and the last fold should be 4 fingers thick. You should have 5 or 6 folds by the time you're done. They should also hug your arm tight, but not so tight that they cut off circulation.
Each time that you roll, your sleeve up, think of it like folding. You want to smooth out each roll and get it as flat as possible. Upon each other fold, keep your fingers and thumb holding the existing folds together. This will help keep wrinkles out.
When you're done, try it on. If your sleeve are too loose, you'll have to do it again. This time lay the uniform flat down facing the deck. Then fold the upper/top part back up so it's facing up. Your crease should be at the bottom edge of the sleeve, across the center of the chest. Depending on your needs, you may want to have a 1/4" or 1/2" of the bottom edge of the sleeve folded up in the sleeve roll... Also depending on your arms, that fold should run half the length of your sleeve, up to the full length of the sleeve. You will have to keep this extra fold tight, maintaining pressure with one hand at all times while doing these folds.
When your sleeves are tight and crisp, they would only wrinkle or bunch up when you curls your arms up, if at all.
Now you should have the sharpest sleeves in your section! OOH-RAH DEVILDOG!
Also, your local Recruiter may be kind enough to show you how. He's just down the street.
USMC Recruiting
242 Bath Road
Brunswick, ME 04011
(207) 729-0067