I see potion utilization is set as blue, but to be honest, this should be green. You can max it for 0 to 100 within half an hour.
Grab some food. make stacks of 1 unit and eat it. Or just take a bigger stack, eat -> move -> eat -> move etc.
At the beginning eating 1 unit bumps you from 0 to 16, then 16 to somewhere in 20s, then it keeps going slower.
Eventually you get 1 level per 1 unit.
Its like how you leveled passive regen back in the days.
Thank you so much for this, Diphling. I've been looking up your guide every time I get interested in a particular skill. I'm not a fan of macros, but the general information of "Skill X rises only when you do Y" is extremely helpful!