I remember how scared I was to try anything when I first started collecting. I would see my friends plucking hairs, stretching legs, twisting torsos and I was fearful I would break something if I tried. How silly I was, lol. Now I flip them all over and twist them in ways you'd never think they should go. No fear, baby!
Give it a try, it makes a world of difference in their posing. I should also mention, I know hot glue works as well though I have never tried it. If you've done it or have some suggestions for people leave them in the comments!
source: http://sparki.deviantart.com/art/How-To-Suede-Your-BJD-83821843