If you are using amphetamines and/or sedatives and prescription painkillers, stop them immediatly. That is what has the chance of screwing you on an employment drug test.
They won't be testing for juice. Don't use the masking agents like someone above stated....most good drug tests also test for masking agents. Testing positive for one of them is just as bad (in your employers eyes) as testing positive for heroin.
Shoot some cocaine before you go take it. Once they see that, they won't even worry about the roids bro. Like Pikey and Bar Room Hero said, they won't test for gear so you should be fine. I'm looking for a job right now (yes, I'm gone from FedEx, so be extra careful with your gear because the guy that took my place is an ass, and he won't let it pass, then you'll be in shit with the cops), and I've had a few drug test. One lady asked me if I had a problem taking a drug test, and I said "No mame," and she said good, the you don't have to take one. At another one, the "Piss-technician" said, "Don't worry, we don't test for steroids." I took that as a pretty nice compliment. By the way, don't eat anything with poppy seeds in it (like muffins, not muffs, but muffins) because they will make you fail it.