I'm always on the lookout improving my productivity. Recently I came across a classification method called Eisenhower matrix which assigns two qualities to the task and helps you decide if you should do it right away, postpone it or delegate it to somebody else.
After reading about it I was a bit disappointed I was basically already doing it. So nothing new for me. But never the less it's still a really good method deciding the priority of tasks.
Basically its about deciding how important and urgent the task is. If it's both you should do it right away. If it's important but not urgent you can do it later. If it's the other way around you can delegate it. And if it's neither it's probably not worth doing at all.
Personally I'm using a third quality in addition to those two: whether there is somebody else capable of doing it. This modifies the outcome a bit, but lets me further focus on my doings and also gives others the ability to learn things.
First of all, instead of doing all important and urgent tasks, if there is somebody else capable of doing those I can still delegate those tasks. Also, if it's urgent but not important I can still do it myself if there is nobody else capable of doing it. But if it's important and not urgent, instead of just postponing it if there isn't anybody else who could do it I can later take time to actually teach somebody else to do it.