[Manco]

A good practice for not chickenscratching and using space effectively is posemaniacs 30 second pose drawings btw since you don't have time to draw a million lines.

Do not use posemaniacs, using 3D models as a reference isn’t as useful as real photos. Here’s a summary of what makes a good reference photo: http://www.freshdesigner.com/good-fi...ference-guide/

Here’s a few sites that let you do timed drawings from photo reference (beware, the links below contain NSFW nude photos!):

http://artists.pixelovely.com/practi...igure-drawing/
http://reference.sketchdaily.net/en/

And some more photo references that you can use at your leisure:

http://characterdesigns.com
http://www.freshdesigner.com/figure-drawing-reference/

Also a nice little summary and some tips for line dynamics: http://nsio.deviantart.com/art/Nsio-...mics-411098876

e: This video helped me out a bunch, it goes over how you can control your pencil to get different lines: