your method makes the difference between if your going to cause an overdose or not by feelgoods method....
Just buy whatever size caps, whatever is easiest to get for you it doesnt matter...
Weigh out the 125, 100, 150mg whatever you agree is a sensible dose for most people, feelgood is right 2mg/kg is the normal (or max??) dose....
So work on a 50-70kg person, use 50kg is better then your safe.... and the users are too...
100mg weight it out, put into cap, then fill the rest with plain sugar or better yet iceing sugar (best and safest).
-AC