i would say that you should get yourself some Quick Fix 4.0, but since you can't buy anything now, dilution will be your only option it seems.

there's a lot of info on dilution, and it usually involves drinking lots of water/gatorade the day of your DT, loading up on creatine in the morning (very important).. taking some aspirin, and then more water/gatorade after every void...

when you go to test, make sure you aren't giving them the first piss of the day as those are usually the dirtiest.. try to go during the afternoon after you've pissed a few times already, and when you give your sample, give it midstream... not at the beginning of the piss and not at the end of your piss.

good luck.