Passing a drug test.

I have an interview tomorrow for a really great job and I'm sure that if I get it I would have to take a drug test. I'm nervous b/c I smoked weed 10 days ago. I consider myself a moderate smoker. I've only smoked a  total of five times this year. I'm assuming I would take the drug test sometime next week. Do you think I have a chance at passing? What can I do to increase my chances of passing??