Freebase is the cocaine that is not water soluable. This is done with powdered coke for snorting. You take your cola and mixed in large spoon or what ever that can handle a flame or heat with a small amount of the cola with some regular ammonia, not the scented type, heat this and it will form into a rock. Rinse out the ammonia and save it the ammonia because you can repeat this once more. Smoke your rock in a foil pipe you make wrapping a piece of foil about 6 or more inches, wrap around a pencil, bend it to form a bowl and smoke away your brain.
NOT RECOMMENDED, as it is very addictive, so you have been warned. Don't flame me, some one else would have told this anyway.