Want to test that you really know your talk?
This is a trick I learned from actors, where it is often called a Chinese run-though. Or Italian run-through. Or [Insert name of language other than the one you speak] run-through. It's typically one of the last stages of rehearsal.
Do the entire talk out loud as fast as you possibly can.
You should sound like one of those frantic radio ads for demolition derby Sunday or the old FedEx ad.
It becomes incredibly obvious where you don't know your stuff, where the transitions are weak. And talking as fast as you can really gets your energy levels up. So do the Chinese run through it as near to the actual presentation as you actually can.