As a teenager, I'd read that you could dip your nails in a cup of cold water to make them dry more quickly, but when I tried that, the outline of the droplets remained visible in the nail varnish. So now, when I paint my nails, I'll wait for a few minutes to let the varnish dry a bit on its own. Then I'll stick my fingers under the cold tap for a few seconds.
I let the water drop down on my skin and then run along the fingernails from there. In that way the force of the water falling down won't deform the varnish.