Here's a (partial) list of newbie boat owner rules:
1. Use the blower before you start the engine. Seriously.
2. Dont forget the plug. Seriously.
3. Don't fight with your wife at the launch ramp. It isn't worth it. If she doesn't know how to back up a trailer, or put the boat on/off the trailer. Teach her patiently. Or let the 7 year old do it.

4. Keep a spare prop in the truck or boat, keep a prop wrench. It's cheaper to buy a spare online before you "need it" than at the marina, and you'll probably need one at some point.
5. DO NOT forget to trailer the outdrive up before you pull the boat up the ramp.

When you get to the ramp, look at the MANY marks on the ramps from all the other guys that forgot to trailer up.
6. Keep it fun. It's just a boat. If it gets a scratch, or a tear, don't sweat it. Kids, wives, friends, they all just.......do stuff to our boats, accidentally. Stuff happens. Seriously, really, if a man gets all stressed, and freaks out about his boat, his family won't be diggin him, or the boat, or the trips to the lake, because they are worried that dad's gonna FREAK OUT! lol Yeah, I've seen it happen, and you'll see it happen at the ramp.
7. ABOVE ALL, be paaaaatient with your family. WIves and kids can be mind numbingly sloooooow at getting in the boat, getting out of the boat, getting their life jackets on etc.
Sorry for being a bossy pants bro. I'm just telling you from personal experience, and from watching other people. A great day on the water can be ruined in moments with bad attitudes. And a $20k boat can bring out the worst in us!
This list may grow....... LoL
All that said, CONGRATS, welcome to the club!