The one rule I have when it comes to docking is no one is allowed to jump off the boat unless it is completely stopped. Being between a 10,000+ lb boat and a dock is no place for your body. The other thing that is very important is to know what happens when you turn the boat. Many people including myself when I first started boating thought the boat turns the same as a car. It does not! The best way to see how your particular boat handles is to take it to calm waters and just steer the boat around an object like an old life vest. Do this at different speeds and directions. If your dock is in a place with a lot of wind or current it would be good to repeat these maneuvers under those conditions. The point is don't do this at the dock where crashing into something can cause damage to your boat or someone else's. Take your time doing this and then practice motoring up to your life vest and stopping both in forward and reverse. By the way, do not let go of the helm when backing as the rudder will slam forcibly to one side or the other and possibly break something. Once you have mastered those skills you will find it much easier to put your boat where you want it without hitting anything. Another thing to remember is neutral is your friend, especially in reverse. With the boat in neutral prop walk and prop wash are eliminated. Another exercise that is useful is to motor slowly forward then idle the engine and shift into neutral keeping the helm on a straight track. As the boat slows to a near stop put the boat in reverse and bring the engine to just above idle and note what happens to the track of the boat. Not only will it stop forward motion but it will start moving backward as you would expect, but it will also turn to port for most boats. Some boats will turn to starboard due to the rotation of the propeller. This is called prop walk and it can be used to your advantage when docking. For example, if you find your boat too far from the dock to disembark you can use prop walk to bring the boat closer to the dock.
Although I don't suggest you do it I have seen people bring the boat into their slip and slow and gently let the bow bump the dock then steer the helm into the dock leaving the boat in forward at an idle while they tie up the lines then get back on the boat and shut the engine down.