This is basically an arm roll to matrix then back to arm roll. So either way you look at it, a steve squished around a matrix, or a matrix squished into a steve.
You roll the staff down your arm with spin, but make it hugely off-center to the front of your body, (rather than a little to the back, like a normal steve.) this will help you to go into the matrix. Then do the back of neck wrap after the matrix and the other half of the matrix normally. I think it helps to do the second half with a bit of slide to get the center point further around, to help you finish off the steve nicely.
You can also do a full steve matrix. But I think it's fairly obvious what goes on in that.
(Right click, save target as... )
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