Let me make sure I understand you correctly, you want to see a hand come on, draw a few elements, and then those elements animate, right?
If so, there are a number of ways to do it.
One would be to get a solid surface the same color as the intended background of your comp. Draw very lightly with pencil on the surface to match the initial start point for the animation (this could be done by using a projector and tracing the outlines). Then the actor would simply follow those drawn lines.
You would then rotoscope the drawing hand and voila! The reason I didn’t suggest using a green surface and keying it, is because there would be a lot of green spill on the actor’s arm. However, if you’ve got a good lighting setup, you could try this too.
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