I have recently done a session where the sub was most interested in being made to wait for his punishment. I have always found this to be a powerful tool, particularly if the bottom is exposed at the same time.
It focuses the mind on what will happen to you and where. Only problem is you don't know when. I could make you wait 5 minutes, it could be 10. It could even be an hour. During that time you may well be tortured by your mind, which will be worrying about what I will use on you. Will I use the strap? The cane? How many strokes will I give you? While you are waiting for me to dish out your punishment you can think of nothing else.
You may even let your mind run away with you. Would you imagine worse than I can dish out? It is possible as the brain is a powerful tool, but I am also quite something with the cane if you step out of line.
After going through the 'letting your mind run away with you stage' you may go through another stage. You will begin to think to yourself, 'It can't be that bad can it? I mean I have been punished before. She is a slender lady so she can't possible hit that hard.' These are dangerous thoughts! Your brain is trying to give you a false sense of security whilst you wait for me.
Better to imagine a punishment worse than that I actually dish out to you than one which is far worse than you thought me capable of wouldn't you say?