Know the difference between retouching for photography and retouching for video. With photography, you're only dealing with a single image so more detailed work can be done easily.
For example, with a still photo, you can use Photoshop's Liquify tool to lift skin and flatten out hunched shoulders. It's an excellent tool for doing that type of work. After Effects has the Liquify tool as well, but it is much more difficult to use with video, especially if the camera is moving. It's probably not possilbe to give someone a face lift on video unless there's a pretty large budget involved or you have a lot of time on your hands. However, you can quickly drop a few pounds off your subject by scaling the video up 5% vertically. This works particularly well with talking heads.