Just started yesterday. I had braces as a kid, so I know this isn't worse, but it's SO MUCH MORE ANNOYING THAN I THOUGHT IT'D BE! You can't snack
at all without brushing your teeth afterward. It's 8pm, and I've brushed my teeth 6 times today.
At least it promotes a healthy mouth, right?
And ortho said 6 months until straight teeth. Not so long... but wahh...

Anyone else straightening their teeth before their wedding? (I needed to do it anyway - crowding was p!ssing off the dentist - but this gave me motivation to actually get it done.)

whatshouldwecallweddings.tumblr.com
Re: Invisalign
I would recommend you get a toothpaste that helps strengthen enamel, brushing your teeth after eating/drinking, especially after something acidic (pop, fruits, spaghetti sauce), will promote enamel erosion.
Training to be the next companion.
As for the Invisalign, I remember when I first put them in, I thought "there is no way I can do this for 6 months." It was ALL I thought about - - and I thought my speach sounded different, etc. You do get used to it and soon you can wear them without even noticing they are there. It does get easier. It will definitely hurt for a few days each time you swap out retainers to a new one, but that just means your teeth are actually moving! As for brushing, it is a pain. I did brush after meals, but honestly, I'm sure there were snacks where I just drank some water and left it at that. Do the best that you can with it.
Good luck!