You can't really speed up the process despite what you hear.
Commercial 'detoxifiers' work on the principle that if you increase urine production you increase the elimination rate of any drug or metabolite floating around the system. So most are just diuretics and you can gain the same effect by drinking a lot of caffeine (plus Coke/coffee tastes better and is cheaper). Problem is, THC isn't water-soluble and isn't really impacted by diuretic use.
HOWEVER - increased urine production does result in very dilute urine... which means that the detectable amount of THC is less per volume. This is sometimes enough to return a result that is below a reportable amount and is considered a negative. Most testing checks for urine dilution though, and if it is too dilute they'll invalidate the sample. So it's a gamble between over-dilution or not enough and ending up postive. [You should also take vitamin B supplements if going this route as it will make your urine look less dilute to visual inspection.]
'Masking agents' have generally not ever worked for marijuana testing. In fact, some labs started simply testing for masking agents themselves along with the regular marijuana test. The presence of a masking agent in a sample invalidates the result and is usually considered a de-facto positive for drug use.
The best solution in my opinion is to spend the money on a realistic looking strap-on type system with a simple heating system and beg/borrow/steal from a straight friend a clean urine sample amount...