Don't tell the child, from the get go, "it's going to hurt! I'll be right back with the liquid nitrogen!"
Don't say, after trying to freeze it off, and the child is still crying, "it can't STILL hurt!"
Don't offer the child a choice, "do you want to get rid of it, or keep it?"
it doesn't hurt, why does she care if she keeps it, when the alternative is pain?
Don't tell the child "anything we do to try to get rid of it will hurt"
Don't KEEP SAYING "it can't possibly still be hurting!" while the child is saying "oww...it's stinging really bad" and crying.
lollipops might work really well as bribes. better than saying "you have to get rid of it somehow, might as well be this way, since all the remedies hurt" MUCH BETTER, I would think, though since you didn't try it, I don't know for SURE.