You don't get to decide your part in the school play, but you do get to decide whether or not you play it well.
Don't expect a stranger to wipe your nose.
One thing you can't pretend to be is funny.
Even babies like to grab for things just beyond their reach.
Don't say "The last one there is a rotten egg": unless you're absolutely sure there's a slow kid behind you.
If the horse you're drawing looks more like a dog, make it a dog.