I'll try a mini-recorder. Or maybe leave myself voicemails.*
* I used to leave myself wake-up call voicemails when I used an Octel system that allowed you to leave *future* messages.
Me: (sleepily) "Hello?"
Me': "Wake up. It's time to go to work."
When I would hear myself dryly saying "Wake up. Time to go to work," I knew I was right. Rationalizing my way back under the blankets wasn't an option -- I'd already decided to get up, right? Exactly intense enough of a strange experience to get me started, without much effort.