Uhm video idk :<
If I find out an easy way to do it, then sure. Otherwise, probably not. Sorry!
I can probably do a time lapse drawing.
As for the marks on the hand, definitely if you're not careful.
I'm right handed, so I usually start shading on the left side of the page to keep myself from getting it all over me. ._.
for instance, in this drawing, first I drew the shapes in pencil, then I overlapped them with pen, then I erased the pencil, then I drew the light source, then I shaded them in this order: heart, club, spade, diamond.
sometimes however, I get carried away and start drawing the shading on the character first, before I decide I want something else in the picture to be dark... so yeah. It can get a bit messy.