Posture, posture,posture! My bub was posterior from 32 weeks - and I was doing all of the above. At about 36 weeks they told me she had moved and was in position and I slacked off a bit with it all - turns out she was still posterior and I ended in cs too...
Lots of great advice here hun and you might want to check out THIS thread - it has articles and resources for posterior bubs and links to the spinning babies website!
Good luck!