What is the simplest way to increase volume of mesh?

Question

This hand looks too skinny. What is the simplest way to make it fatter, especially the fingers?

Answer 1

In Edit Mode, you can use the Shrink/Fatten tool. ⎇ AltS
It is limited to the selection.

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You can also add a displacement modifier and change the strength value.
For more control assign a vertex group to it. Create a the group and go into weight paint mode ⎈ Ctrl↹ Tab to paint the weights.

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