Diluting your urine isn’t a good option for 2 reasons.

Firstly, drinking more water/juice or whatever in the days leading up to your test will not speed up THC removal, as it simply isn’t soluble in water, and secondly your reduced creatinine (colors your pee among other things) from drinking so much water will likely also show up and indicate dilution, which is a common indicator of and attempt to mask ‘substance abuse’.

Exercise can be helpful in the weeks leading up to a test, but again increased activity over the short term will only increase THC release as your fat cells break down. The most important thing to consider, as was previously mentioned, is that some of these so-called herbal remedies also contain substances that are being tested for. In truth only time and exercise will rid your body of THC.

I’d be loath to recommend using someone else’s sample. Your best bet would be either to refuse to test on 4th amendment grounds (yeah right ^^) or to ask for a retest if you are found to be positive.

A retest might also offer you time to get yourself as clean as possible, and that is ultimately the only answer if you work in a climate where drug testing is commonplace.