I won't add to the specifics everyone else noted, other than to essentially agree with them. I will add one rule I try very very hard to follow since I single hand almost exclusively. I do NOT leave the boat until I have it secured. Secured usually means a minimum of one line tied if that line will stabilize her position, so in the worst case scenario, i can't actually lose the boat. At 48 feet, I can't manhandle the boat. This rule sounds simple, but sometimes its not. I may mean that I have to quickly get back to the controls, if I miss my window to get a line on the dock. I don't take the chance of hopping off with a line or two in hand under the assumption that I always have enough time to get at least one tied. Sometimes...you miss. If you do, I'd much rather be on the boat with options than on the dock watching helplessly. It can take longer to tie a boat from the boat than from the dock, so you have to factor for that. It means you might only get one line on instead of two before returning to the controls. This means you have to think about what you likely will be doing when you return to the controls after tying that one line and maybe have rudder set up before you leave. As always, single handing means being very good at planning and contingency. You have to know what your trigger point will be to abandon and go to plan b before you get to that trigger point. If you don't, you will find reasons to take chances you can't afford and wind up in a spot with few options.
For my boat, the easiest line to tie, the one I have the most reach is from the swim step, often kneeling. It follows then that if I can't get any other line on, I'll be trying to find a way to bring the stern closest to the dock, get as short a line as possible to maximize line leverage and then often I'll return to the controls and use that tied line as a pivot point to force the bow in using props and rudder. It means that LINE PLACEMENT takes precedence over what otherwise may be your preferred landing orientation if you can't ensure you can manage your line placement otherwise.
The stern line is not my "favorite" line for overall control, a well placed spring works MUCH better, but only if you can get one on. I can get a spring line on pretty quick and effective if a dock has cleats. Many of our docks in the Pacific Northwest don't have cleats, since we have floating docks piles may only be on the ends too, often its just wood bolsters you have to loop a line under and I don't do that well from 6 foot away. So again...back to the stern line, the one line I can most likely reach from my boat.
Once I have that one well secured line on, I'm willing to leave the boat, sometimes even with a single prop still in gear if that is the force needed to stabilize movement against wind or current. That may sound like a risk, but I consider it much LESS of a risk than stepping off a boat with two lines in hand with the boat nice and parallel to the dock. I've seen things change much much faster than I would have imagined possible and now I just try very very hard to avoid it.
So....consider the not leaving the boat rule and see if that changes how you view your options.
