Justin writes:
Learn how to make yourself look old by adding 2D geometry to match the movement of your face markers and then painting an image onto the geometry as an overlay onto your face.
I'm OLD! (in Blender) TEASER
Make yourself look OLD in Blender | Your Face
Change your hair color in Blender | Part 1 - Simple Masking
Change your hair color in Blender | Part 2 - Advanced Masking
Change your hair color in Blender | Part 3 - Animating Masks
Change your hair color in Blender | Part 4 - Masks & Color Grading in the VSE