Say no: Politely decline
This one is genius. He’s asking the favor, but you thank him for thinking of you as you firmly close the door. It works with just about any kind of request, and the asker rarely knows how to respond—hence, no push back!
Say no: Suggest a smaller commitment
Here you’re making it crystal clear that you aren’t available for the task being pressed upon you, but you’re not completely blowing off the person in need either. No one can hate you when you’re offering to lend a hand elsewhere.