RUNNING FOOL

[Sketchasaurus]

I could never quite grasp the concept of the head measuring system, how do you determine someone height? Is it a combination of the number of heads and the size of it?

Heads are just a way of measuring someone's proportions, not necessarily their height. you would measure a character's proportions based on the size of their head. a character that's say, 3 heads tall proportionately, still can be taller than someone who's 8 heads tall. a good example is the difference between The Thing and Mr. Fantastic from the Fantastic Four.

I say that you're off to a good start, PK. though, I'd try drawing the lady from different angles and different poses. the best way to understand anatomy is by learning how things look when they bend and move.