If at all possible, cut an inch off you hair as well. Your working with over a half an inch of clean hair and atleast an inch of dirty. Collectors will usually look for a sample atleast 3\4" long. Your head hair grows faster than your other body hair so you want them to take the sample there. By taking an inch off, you remove alot of excess thc hair follicles that could cause you to fail. Other than that, I think your on the right track. Good luck and keep us posted.