Over the years I've learned a lot about docking single handed, and there is a major difference between how the varios keeled boats handle backing up. For example, when I had a Catalina 27 with a fin keel and tiller steering, I would put the engine, Atomic-4 inboard, in reverse, gun the engine a bit, shove the tiller hard to port and within seconds the boat was manueverable and I was able to slip into the pier just like I was parking a car. It was a piece of cake.
Now I have a Morgan 33 Out Island with a full keel. Full keeled boats are much more difficult to manuever in reverse, and often they just prop-walk in various directions with no steerage in reverse. YES - different directions of prop-walk. I know it sounds weird, and most folks would scoff at this, but when I experienced it, which has been on several occasions, I was flabergasted.
Consequently, I try to utilize all the elements at hand, wind, tidal currents, prop-walk, etc... It took a bit of practice, but I'm now at the point where I think I could park this hull in any slip where I have 10-feet of fairway clearance - I've done it a dozen times during the past two months and under conditions where people on the docks are amazed. When I docked at Saint Augustine City Marina, a location where the tide screams through the floating docks, the dockmaster asked if I would nose into the slip just to be on the safe side. I said I would rather back in to facilitate easier departure in the morning when no one would be there to assist me. I correctly gauged the wind and current, slowly eased the boat into the fairway, cut the wheel hard to port, and when the boat was 10 feet from the boat opposite my slip, I quickly put the transmission in reverse, turned the wheel to starboard and gunned the engine. The boat came to a stop and with a bit of forward and reverse jockying and, of course, steering hard to port and starboard at the same time, I was able to back the boat directly into the slip, never touched a piling, and stopped it a foot from the pier. At that point the dockmaster slipped a line on the stearn and I proceeded to tie off on the pilings. All of this took less than 2 minutes, but when you're maneuvering between yachts that go for several million dollars each it sure brings out the pucker factor. When I stopped the boat there were a dozen people on the dock applauding. I'm not sure if they were applauding my docking skills, or applauding that I didn't damage their boats in the process.
Bottom line - go out to a soft marker buoy and practice backing down with your boat to that bouy from various directions. Learn how YOUR boat handles in the wind and tidal currents, and what is the best method of approaching. It takes a bit of practice, but in the end you'll feel a lot more comfortable when entering a strange marina.