When people are looking for single-handed sailing tips, there tends to be a focus on changes to the boat- with sail controls and self steering being one of the primary foci of the discussions. While these are useful discussion points, to me the biggest issue is one of choreography. The central issues with single handing all revolve around the "How can you be in two places at once?"
Acknowledging that you only have two hands, two knees and two feet to do things with and that they are all (ideally) attached, the first step in learning to single-hand any boat is to break down any maneuver that you are likely to do into a number of discrete steps and then arrange these in a sequence that minimizes the need to be two places at once, reduces the time and effort to perform the maneuver, and eliminates much of the chance for a disaster to occur.
The boat's behavior, deck plan and hardware certainly play a role in this, but once the reality of these are factored in, the ease or difficulty is often driven by where you place your body, how you move around the boat performing the required tasks, and the sequence and timing of each step of the maneuver.
Part of developing these step by step processes is making sure that the maneuver happens a reasonable rate. There is a tendency to rush through maneuvers when you are single-handed, trying to match the speed at which the same maneuver is performed on a fully crewed boat. That often results in a longer time to complete a maneuver or more effort. Instead plan the maneuver in a way that allows things to happen slowly enough that you can safely move through the process. I sometimes hum waltz music to slow myself down.
But doing maneuvers more slowly than a fully crewed boat maneuvers also mean leaving more searoom to perform the maneuver than a fully crewed boat requires. Simple items like tacking do not need all that much more space, but mainsail, jib and spinnaker raises, jibes, and dowses can easily eat up 3-4 times the distance required by a fully crewed boat, especially in a stiff breeze.
Which brings up another key piece of single-handing; thinking things through long ahead of time. A part of thinking things out ahead of time is practicing tasks in a place where you have plenty of room to avoid getting in trouble, but also practicing tasks in a mindful way. Start your practice maneuvers near a reference mark and by clicking off a stopwatch, Then, at the end of the maneuver make a point of looking back to see how far your traveled from that mark and how much time has passed. (You will be amazed). But by practicing enough, you will be better able to predict how long it takes when it goes right and when it goes wrong.
Once you have a sense of that, it is easier to avoid placing the boat and yourself in a position where there is no where to go but into trouble. Here are a couple single-handing pictures:
In this first picture I have just rounded a mark and I am heading up onto a beat in a building wind. The chute was dropped early before the rounding and the jib set up for the beat in the last 25 feet on the run. The traveler and backstay was preset, and then the main sheet was hauled in as I made the turn. At this point the boat is a little overpowered so I am in the process of dropping the traveler (one hand on the wheel and one hand in the traveler control line)
This second picture is beating out of White Rocks in moderate winds. I am sitting at the jib sheet winch, wheel in hand, the traveler control line and mainsheet are just forward of where I am sitting.
This last shot is reaching through the Bay Bridge I am roughly 2/3 of the way towards the windward pylon. This allows me plenty of room to bear off in a shift, or a little room to round up if hit by a big gust.