P.M.
Here's a highly informative website you might find helpful. It gives a few variations on"readiness" checklists, plus tips on various training strategies used in various cultures around the world, the best ages to start them, and the advantages and disadvantages of each approach: http://www.parentingscience.com/potty-training-tips.html
Another thing you might be able to do with her is to teach her to crouch, though she might be a little young for this. But I know of a little guy who couldn't really poop sitting, but was able to stand on the toilet seat in a deep crouch and successfully poop.
Good luck!