Aaaah I've just been reviewing my dvds and scribbling notes about this. It will come.

As you take your first step on the right foot, begin a basic shimmy (up down up), as you switch the weight to the left foot finish the shimmy ( up down up).

You will have more range of motion in your right hip beause of the way the right hip is placed.

Its better to start them slowly.

What helped me was to get my arabic going and slowly and consciously add the shimmy aspect.

Now for me its automatic and I have to physically stop me from shimmying with it.

(just posted this on the ATS tribe!!)

i would suggest practicing the shimmy slowly at first on one foot, then the other and picking up speed as long as technique is correct. then i'd recommend holding unto a barre or wall, and practicing the same on the balls of your feet, and then on one foot (while still on releve) and then the other. correct technique is key here, and more than anything, having full control of whichever shimmy speed you choose. you may then want to add level changes and walking with it (flat footed and on the balls of the feet). though you may have a really good 3/4 by itself right now, its always good to go back to basics to make sure that its not a technique issue...

once this is nice and strong, *slowly* add the undulation, again at first flat footed, then on one foot, then releve on both feet, then releve on one foot--adding level changes for good measure. holding unto a barre can be helpful as you really focus on the movement rather than balance, etc. make sure the undulation is small and controlled--at least at first--again, correct technique and posture are key here.

besides this, its all about practice... :) good luck!!!