A nice smile is the best you can wear?

They say that a nice smile is the best thing you can "wear", to make people interested in you.

What to do when you have a "resting mad face"? The male equivalent of resting bitch face.
Even when I smile I feel it doesn't look genuine and when I try to take pictures to get used to it, they look very awkward to me.
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+1 y
I know then saying is actually "best makeup", but I guess it would apply like this too.
A nice smile is the best you can wear?
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