
Thomas S. answered 04/18/19
MFA in Studio Art. BFA in painting/drawing. Thomas Saffle artist.
Great question. Wish there was a quick answer to this but unfortunately there is not. Drawing the human figure well(realistically) from the imagination is one of the hardest things to do in the realm of drawing. The required knowledge of anatomy and how to apply this to a limitless number of human body types and possible poses is truly daunting. However, it is achievable with time, effort, sincere interest, and what may be called talent or natural predisposition.
Drawing figures well from the imagination will be determined by your experience drawing from reference. Your mind will not be able to simply come up with missing information for your figures and must be based on something. At first the best thing to do is to look for references for the figures you want to draw and if you can't find what you need online, in a book, or wherever... is to make one yourself. Take photos of yourself or others who can be posed appropriately for your needs. If you keep drawing steadily from references and from life over time you will build your visual knowledge and drawing from the imagination will become easier and easier.
Hope this helps.