Take a private lesson with the teacher to cover JUST that move. If you can't find it anywhere else, go straight to the source.
It is possibly what I call the "Denise Walk" named after Denise Enan who often throws it in when she is improving. A group of us sat down one day and tried to work out what she was doing. Now, this is quite possibly NOT what your teacher wanted but it's a lovely walk.I thought 3/4 shimmy and this "egyptian walk" are the same thing, but now I'm not sure. Earlier I had tried to do the movements consiously. Most resourses seem to emphasize the hip movements and the pattern the hips are doing, but my teacher just said not to concentrate on the hips, it's all about weight shift anyway.
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My teacher spesifically pointed out, that I shouldn't be doing them, they just happen. But not on me.
So what shimmy walk could this be?