I sail my 41 footer solo about 90% of the time
It's all about practice and more practice
Get out in open water and lock your helm/rudder in a straight position
Grab your gib line in one hand the main in the other and try to get a feeling of how your boat will react when adjusting one or the other
At first it will be erratic ( that's why you went in open waters
But the more you practice ....
On my boat it's also about balancing sail sizes
The boat is easier to balance when using a 120% gib rather than the 150 and using the 90 with a full main when going upwind
Again you need to practice and try different configuration each boat is different
Recently did 60 Miles to Ptown without having anything to do except read a good book and enjoy a smooth sailing .
Always amazed when I read stories about crews abandoning ship after they broke or lost rudder . Even in good sea condition. Practice seems to be the key