Tried to mix it up a little here with some extreme foreshortening ie, a flying figure in the bottom left hand corner, a bent over figure; top left and a view from slightly above; top right. I've also included some sketches that made it to final artwork and some with just muscle detail.
With the exception of the top right pic, these are some full body shots that I've kinda simplified in order to pic out the physiques. Although most of the reference I tend to use is based on swimsuit photos, I try my best to draw the figure through any clothing, it helps make you think more about the basics of the figure by drawing what you can't see. Dunno if that makes sense but... I guess in my opinion once you've got the the figure correct you can then add the uniform, costume, clothing etc and it should all look correct.
It took me a while to make this simple tutorial of how to make figurine hand. Wish I have an extra hand to take pictures... It is pretty much self explain of step by step in the picture comparison. Although it looks simple but you do need the proportional conception of human's hand and fingers in mind. And also compare with the character that you are making. Make a good calculation for the size, think it over through, get it right at once.
Please note the nail should better be made from the beginning of each finger. You might not get a good position to sculpt the nails when putting fingers together. Only if you are making large size hands.
The picture shown with a shape knife meant when you going to bend the fingers. Make a shape cut but don't cut it off! Pull it up a little, bend it and fix a bit for the gaps after you bend it.
I make it in small scale so you may use the same skill to make larger hands. Hope this may help you a little. Please advise if you have any suggestion or question. Thank you for watching my friends! Enjoy!!