I dont know why all of your bastards are making fun of this poor kid. He asked a serious question and at least I gave him a serious answer.
Now patkob, due to the high amount of "s" you are going to be injecting (20,000mg/week) You are going to need to inject about 17 times every day.
I know, it sounds intimidating, but take a page out of amaf/uou/m0f0's book. Fill 8cc of "s" into a turkey baster and coat it with either deca or vaseline for lubrication. Slowly insert it into your anus and squeeze the end so that all of the "s" gets into the body.
WARNING! Be sure to NOT releaze the squeeze thingy at the end of the baster when it is still in your anus. This will create a vacuum and suck all sorts of feces and bodily fluids into the baster. This will result in the need to purchase a new baster, and due to the amount of cash you will be spending on all that "s" you need to save all the money you can.