How do you do this?

[Michael Szalapski]

That is usually done by rotoscoping. That is, cutting the person out via masks. There are many ways to make it easier than animating frame by frame.
This page has lots of useful rotoscoping resources: https://helpx.adobe.com/after-effects/using/animating-shape-paths-masks.html#rotoscoping_introduction_and_resources.

After Effects has a tool called the Roto Brush that can sometimes be useful. It’s not as intuitive as it looks though.
Here are some resources on using it: https://blogs.adobe.com/toddkopriva/2010/04/roto-brush-in-after-effects-cs.html

– The Great Szalam
(The \’Great\’ stands for \’Not So Great, in fact, Extremely Humble\’)

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