Drug test tomorrow...

I'm not REALLY worried, I took a few hits of schwag a few days ago...I have the piss test in about 14-16 hours...is now a safe time to try to exercise the THC out of my system? Any tips? I heard something about aspirin...any specific liquids I should be drinkin'?

Also, how do they determine if a sample is diluted? Is this just based on color, or do they determine this after they test?

Forgot about personal info...
I'm 15, 135-137 pounds, 5'10", male.

Thanks for the help and feedback, guys. I really appreciate it. I'm leavin' now to take it, and all the advice I got here leaves me with no worries!

I've heard of eating gelaton (sp). Let us know how it turns out.