I've got an AK-47 with a sling, and I'm just wondering what's the proper way to wear a sling. It just doesn't seem that comfortable. Even when I've got the sling set up to be the longest length possible, it feels tight when I try to shoulder the AK while still slung on my shoulder. Is this proper procedure? Should you take the sling OFF your shoulder before shouldering your weapon? How do you determine what length is right for you? And ultimately, what should the sling be used for?

Thanks guys. I'm a sling-newbie.

A sling for a combat weapon is used for carrying the weapon when you aren't presently engaged in shooting people, think of it as a holster for your rifle.

There are 2 methods of carry with a basic  point sling; american- strong side carry muzzle up and african- weak side muzzle down.  Each has its tradeoffs.  

The african carry is fast to get to in a hurry but you have to watch your muzzle as you can drive it into the ground when you kneel or sit.  basically you have  your weak side hand on the foregrip then are you rotate the weapon to bring it up the sling will naturally fall off of your shoulder.  That's the type of carry i prefer.

Of course if you're talking about a shooting sling (which you're not since this is for an AK) then your talking about a device used to help steady the rifle when shooting.

And then there are 3 point slings which  facilitate carrying the weapon at your front without any hands, handy when you have to transition to a handgun and single point slings.

Actually a sling is vital for a combat weapon so its good that you are asking about it.

Look here:

Sling Carry Options

Most of these also apply to a normal, two-point sling.

That's exactly the info I needed guys. Thanks!