The influence of the deformers that sculpt the face is tempered by paintable weight maps. You can use maps to control how the skin wrinkle and folds.
You can access and paint different weight maps from the Face 
Maps tab on the Tune panel, as well as from other areas on the Tune panel. The different weight maps allow you to modify each
region of the face in relation to the Strength values you set for the corresponding region deformers (see Working with the Region Deform Areas).
See the following sections for more information on each type of map:
Here are some general tips and shortcuts for painting weight maps.
To adjust the paint brush properties:
Press R or use the mouse's scroll wheel to change the brush radius interactively.
Press Ctrl+W to open the Brush Properties editor in which you can set all options.
Use the right mouse button or press Shift+left mouse button to remove weight.
Press Alt+left mouse button as you paint to smooth weight values between points. This is especially useful when deformers create sharp creases. This creates a smoother falloff for the painted region, resulting in a more subtle deformation.
Select the Interactive Refresh option in the paint tool to update as you're painting instead of updating only after you've finished a brush stroke.
Press Esc or the space bar to exit from weight painting mode.
