You have to shear your goats in order to show at the 4H Fair where i live so i will be doing it this summer. I plan on locking them into a milking stanchion and then shearing them that way.
My kids have to shave their 4-H Market Goats in order to show them. Lots of people use big Oster Clipmasters, and I have a pair, but IMO, they suck for shaving goats. They are just too big and bulky, and tire your hand and arm out. Instead, we use a pair of 2-speed Andis clippers and a 7F or 7FC blade. Works great, cuts like butter and the clippers are nimble enough to reach all the areas.
As for confining the goats to shave, you could certainly use a milking stanchion if you are just clipping them at home. For showing, it is easier to use a grooming stand, because it allows you to clip all the way up to the ears/throatlatch and keeps the goat more immobile than a milking stanchion. A grooming stand locks their head and neck in place.