I personally don't believe there is a "right" answer for this. Each person is different. Dosing usually has to do w/ individual sensitivity, metabolism, mind set, and desire. For "most" people I think 20-40mg is probably at least close to average. For some it's higher while others it's lower. My suggestion is to experiment in order to find what you are comfortable with. Start at 15mg and work up by 5mg until you get to a comfortable desirable place. Or, if you really have no worries or fears and want to make sure you break through feel free to start at 65mg (that's where I started). It won't kill you. But, be aware, it can be EXTREMELY intense and if you have never had any experience with strong psychedelics it could be so bizarre and foreign that it is far beyond anything that you ever expected and it could scare the holy livin' hell right out of you. Again, in general, I would suggest 15mg to start and work up to find your limitations.
"A man's got to know his limitations." - 1973, Clint Eastwood as Harry Callahan in Magnum Force