Re: New boat owner!
Don't approach the dock or anything else faster than your willing to hit it. That is the best advice I gave my wife as I was trying real hard to be patient while she was learning to dock. She still is not very smooth, but at least she doesn't come in screaming anymore..
Also, if you don't already have one, put a depth/fish finder on that thing. Its easier to use that to see how much water is under you than to use the outdrive.
As far as launching/retrieving, develop a routine and stick to it. That way you will not forget things, big or small. I notice when I make errors, such as driving up the ramp with the outdrive down, is when someone volunteered to help me that isn't normally there. I deviate from my routine and poof.
When coming in to dock, inform your passengers to stay put until asked or the boat is tied up. The natural inclination is for people to reach out and grab the dock or to get up and move to help. First this is not really safe because of the shift in weight, but it also screws up your approach due to the weight shift. Also, it is common for people to rush off the boat when your not quite done. My passengers do not leave the boat until we are tied up. You don't have to be a jerk about it, but it does help to make that clear when docking.
If the boat has not been used for a couple of weeks, start it on muffs in your driveway before heading off to the ramp. Thats a better place to find out you have a dead battery or a starting problem than sitting on the ramp with all your passengers suited up and the other boaters waiting for you.
Just run your blower all the time. Don't bother turning it off at high speeds, you just may forget to turn it back on.
Those are some of the things I probably learned the hard way.