I like the overall studies and really love how some of these have turned out. However, I would suggest to break your practice sessions into stages which would give you immediate feedback. Stage 1 : Primary head shape/form with brow line, eye line, nose line and chin line. Make sure that they are tracking well in perspective. (1-2 mins) Stage 2 : Simple blocks for secondary forms (e.g. Eye Socket with eye balls, pyramid/wedge for nose, barrel for mouth etc.) (5-7 mins) Stage 3 : Refining features and may be adding lighting, if you prefer Here are some links that I found helpful . https://www.youtube.com/watch?v=afIIuW5aJnk https://www.youtube.com/watch?v=2T7cDY7YDsg

There are some paid apps on iPad for medical students by 3d4medical which might help. There must be other 3d models online too. Here are some screenshots from “Essential Anatomy” that I refer to.