Make sure you stay hydrated, [gatorade, water, or orangejuice] NO SODA. it will only make things worse. you will get a tiny sugar high than feel even worse tahn before you drank the soda.
Make sure you have plenty of fresh clothes, towels (i would sit and soak in the tub 4-6 times a day during withdrawal) Stock up on movies to keep you busy, stay on this site etc. Just basically do things to make you as comfortable as possible (i know your probably saying wtf is gonna make me comfortable you b1tch!) Its basically just things to make you less UN-comfortable I guess.
Another huge thing, dont hold back...if you feel like throwing up or dry heaving...DO IT!! it will suck for the 10 -15 minutes you are doing it but afterwards you will feel so much better. If you feel like bursting into tears or screaming at the top of your lungs because your so pissed off than go ahead. You have been numbed for a long time and these emotions need to get out.
When the anxiety gets real bad and you feel like you've been "fighting and sick" for so long and you start reaching for those pills call somebody close to you or come on here into the chatroom and talk. Remember, IT WILL, WILL pass. its just a matter of holding on for long enough to let things get better.