Just a few thoughts on steering, mostly in docking.
First, if you keep everything as slow and simple as possible the whole process will be easier. That's why locking the motor and steering with the tiller is imho the best way to go in most situations. If you keep the engine at a slow but steady idle, you can just shift back and forth from forward to neutral and reverse without adjusting the throttle. This eliminates moving the throttle around and shoving the engine position around. Generally all the motor needs to do is get the boat moving to the minimum speed so that your tiller can bite into the water. If you adjust the throttle a lot, things can happen very fast and you can get moving surprisingly fast when you don't want to. Second, and for this reason, if possible operate at idle speed, and use neutral when you can. This will mean that you will move relatively slowly, and will have more time to plan and adjust. Once you are moving in the right direction, think about drifting along in neutral and just steering yourself in. Sailboats have a long drift, and once moving will move easily over a longer distance than you might expect. Moving slowly eases anxiety a lot because if buys you time. Plan ahead when steering, and take into account where the wind will want to send you. Boats vary a lot in hull configuration, and every boat pivots around a different point. Always keep in mind that if you are going slow, you will have an easier time of managing any impacts. (Naturally, going TOO slow will rob you of steering, so there is a limit to this principle. However, generally slower is better as long as the wind is not moving you around too much.) Third, going in and out of your slip several times as a practice is very helpful. Not much fun, but I guarantee that if you take your boat in and out of the slip ten times you will feel much more confident on the eleventh try. Most people are so glad to get the boat safely back to the dock that they never make practice runds. Depending on how your slip is configured, you might find that backing the boat in is preferable to bow-in. When you are returning after sailing the boat you are up to speed on your boat and have reminded yourself of how everything works. Thus,complicated maneuvers might be easier to make than they might be when you are just starting out. Among other things, you will not forget about lines tying you to the dock when you are coming back! Usually, leaving the slip bow first has the best chance of just letting you cruise out without changing gear. If the wind is favorable you can just put the engine in neutral and drift out of the dock sometimes if you are pointed in the right direction. Fourth, get your dock lines all set up on the dock for your return, and have lines ready on the boat as well as on the dock, with a boathook handy. You might want to consider running a line from the middle of your slip to the pilings at the end of your slip, if you have them. This v-shaped rig, in the appropriate level above the water, will cradle your boat and let it sit in place at the slip while you are fooling with the lines. It will also let you tie a bumper to the spot the where the bow ends up. These breastlines use up a fair amount of rope, but it's nice to just cruise into the slip and bump gently into the lines and end bumper if you need to. Breastlines may make singlehanding easier as well.
Although this may seem like a lot to consider on this specific topic, these are all factors that will make steering with just the tiller easier and more likely to be all you need. Among other things, engines sometimes fail, and using only the tiller may be what you are forced to do.
One final note. Make sure that your engine kill line is easily accessible! If your motor sticks in the open throttle position or will not move out of gear, you want to KILL THE ENGINE instead of struggling with it and ramming into something. If you kill the engine, you will not be distracted by a roaring engine, your decisions will be simpler, and you can expect to slow down over time and minimize damage in docking. Play with minimizing engine use and you will be surprised how little you really need it.