I know I'm finding it really helpful, I've had a few false starts on this diet but I'm powering through, surprised at myself tbh, but these forums are such a help.
I ordered some ketosis sticks on Amazon, ketosis is the whole your body starts burning your fat for energy thing, when it does that your body produces ketones, you pee on a stick, if it turns pink there's the ketones, so you know you're burning fat.
Lots of info around on it, don't get confused with it all though!
Good luck to you, how are you finding your first day?