The only thing I measure is nicotine with calibrated cylinder. For 500 ml bottle of base - 12-14 ml of nicotine. Then - PG, directly from bottle to bottle, no need to measure, I can see it level. Then top it with VG. Flavors - by drops (I
buy flavors only in dropper bottles). It makes life so much easier. Fast, almost no cleaning. It helps I use only slightly flavored juices. To prepare 50 days supply of
juice (of 5 different flavors) I need less than 15 minutes.