I need serious advice!!

hey guys so im new ive never used suboxone b4 and have no clue what im doing, Thursday im starting subs to get off of dhm tablets which r like mgm15 but weaker,I have 8mg tablets that are hard to break down evenly so .y question is whats the best way to do lower doses? ive heard of volumetric dosing with water but if I do that do I just put the water/sub mixture under my tongue and let it sit and does mixing with water make it weaker? I honestly have no clue how to take them because a buddy of mine knew I needed help and he gave me 16 of them. thank you in advance to anybody who responds and I would greatly appreciate any help and advice!!!! im doing a rapid 5-7 days max taper and will not use longer than that cuz i heard sub wd is terrible