For drawing the head, I use the Loomis method with some personal changes.

I start by drawing a circle, then I add another one to divide the side of the face (red) — think of it like splitting a cheese with a knife.

After that, I work on the eyes and the other facial features. One thing I like to do is draw the glabella (green) to help guide the placement of the facial features. I find it really useful!