Speaking of that, what IS the best way to rotate your leg from your hip? I hear that mentioned for riding, for walking with your feet straight, etc, and I've had only limited success figuring out the best way to rotate from the hip -- especially for riding. It usually ends up with me grabbing my thigh and physically rotating my leg, and although it feels great for a bit, my leg soon slips back out again.
There are lots of things you can do!
I think the first thing to do is to play with thinking about your leg as a unit from the hip. Try standing (or sitting, even) and working to turn out -- lift your leg up in front of you (doesn't have to be high; if you're standing, you can just push your leg straight out in front of you and point your toe so just your toes are touching the ground). Experiment with being very clear on the foot coming straight out from your hip, kneecap towards the sky -- this is, in dance parlance, called "neutral" -- then, with your leg as one unit, rotate from the hip so your heel is pointing inwards and up -- looking like a ballet dancer pointing your toe...do this slowly, five times on one leg, then five times on the other.
I'll come back with more; but at the moment, husband, neighbor, and martinis are calling!