I commend you for looking for advice and input in regards to parking and docking your boat. I'm currently on my third boat with nearly 20 years of boating, navigating and driving experience.
A couple of things I noticed and agree with on this thread...
When approaching a dock, consider the wind and current, if you use either to assist you in getting in closer to the dock, use it! I've used the wind numerous times when approaching the dock from whichever side. It's as easy as getting in close and shutting the engine down and letting the wind do the rest.
This also works very well when trailering the boat. Most of the time I will tie the boat to the dock, back the trailer down and manually pull the boat on to the trailer. If the wind is cooperating, I will use it to my advantage.
When driving in reverse, keep in mind that whichever way the engine is facing, is the direction the back of the boat will go. A lot of times this is forgotten. Whenever I look behind me when reversing, I know that whichever way the cowling of the engine is facing is the way which the (back of the) boat is going.
I use this method all the time when parallel parking a boat. I run the nose in to the dock at a 45, kick the boat into reverse, and crank the engine to point at the dock. As long as I'm nearly sitting dead in the water with a slight forward movement, this works every time.
I think the best piece of advice I can offer is twofold;
1) Don't go anywhere near a launch on a weekend, especially a long weekend. In only the last month or so I've had to help out two boats with either trailering or launching. Both of these people decided to go out and "practice" on a weekend. Bad idea.
2) Get out there and practice and have fun! The only way you'll ever get good at it is by practicing and experimenting. Eventually you'll get a feel for your boat and you'll become confident in your abilities.
Also, DON'T FORGET TO TRIM UP YOUR ENGINE WHEN PULLING IT OUT!
Have fun!
Scott