[Chris Saper]

Any way you want.

I really think that the painter has to communicate at a very basic level. The questions (at least for me) go like this:

"I see that your daughter's left eye is "lazy". Would you like me to convey that in the painting?"

Or, "I see that you have a scar on your upper lip. How would you like me to depict this in your painting?"

Or any such thing; just engage your client in the process, and do your best to meet their needs.

Ask your client!