There are many ways to do it. I like to add it to the keg. I boil a cup of water and let it cool to about 180-ish, then dissolve a half packet of gelatin in it. Once dissolved, I pour it in the keg, no need to cool, and rack the beer on top of it and toss it in the kegerator. I have crystal clear beer in a few days.
(~):} Just a little Furthur (~):}