I have always used sure jell and gatorade. If you are a vegetarian or vegan this will not work b/c the animal products in sure jell. If not, you want to get a 32 oz lemon lime gatorade and drink a little out of it (enough room to put the sure jell in there). Sure jell is the powder stuff that makes Jelly...not Jell-o. I usually get the yellow box, you can find it at most grocery stores including wal-mart. Anyway, pour the sure jell into the gatorade and shake it up pretty good. Then chug it down. Now, your first pee and ONLY your first pee will be clean.

Hope this helps.