@malcom These are mostly sketches I do at lunch time to sort of mindlessly draw and not worry too much about being correct. So I tend to not have any reference (which is why you'll notice the designs tend to be really loose, and somewhat random) Kinda just drawing on autopilot.
Here's some more stuff from this week.

Hey Paulo, agh don't know how comfortable I'd say I am but I did do a lot of figure drawing in college, and over the years. What did help the most was figure sculpture. I did a life size figure and several smaller figures, understanding the body in 3D will help leaps and bounds in constructing a body from the imagination. The rest is all just remembering proportions and perspective as well as what sort of detail is ok to leave out. Essentially, think big shapes first and think in 3D, it'll be a big help.
Here're some more sketches from the past couple of days.