I am still hesitant to mix my menthol crystals from wizard labs.. Some people eyeball the measurement and say fill a 10ml bottle halfway then add pg to top of crystals, others say crush it up and fill to just under halfway in a 10ml bottle.. I haven't decided how I will mix it. Part of the reason why is because I wouldn't know how to add it using a calculator. I want to compensate however many drops I add to a flavor mix with the total ingredients. If I just add drops to a premixed mixture, the percentage of nicotine, flavor and other ingredients would be affected (reduced). Does anyone have a guideline to follow? How to mix the crystals and what the percentage base of the crystals would be?