In my recent post on Instagram most people answer "feet and hands" to the question What's the hardest thing to draw for you?
I have to admit that feet are like a weakness for me. I often need references (my own feet or photos) if I want to draw them properly, exactly like hands.
Here is a quick sheet where the base concepts are shown!
I hope you find it as useful as I did! (and sorry for my horrible handwriting, next time I'll type it directly)
Have a nice day/night!