what is best way to dilute drug test or cleanse system? (heroin)

[rich420]

My friend was using everyday for about 11 months. My friend then went on a 21-day methadone program, my friends last dose was around August 16th. My friend then used Aug. 25th (used 4 days in a row) to Aug. 28th maybe (no more than .2-.4 between my friend and his partner). Then again on Sept. 3rd, and today the 10th. Again, no more than .4-5, 5 being the max, but my friend really don't think that much. Most times was maybe .2-3 between my friend and his partner.

So I have these questions, please answer the questions directly, they are 2 seperate questions (not relating to each other).

How long do you think it would take for it to get out of my friends system to safely pass a drug test?

and

What would be the best way to dilute urine for a drug test? (specifically heroin if there is any special tips for this)