You have to think 2 or 3 steps ahead. It already starts with the approach, the angle shouldn't be too big. With full rudder to one side, a fair kick ahead with the main engine and a bowthruster to the opposite way you can get a fair 'side walk'. Keep an eye out on the speed though.
Needles to say that docking when you are sailing ahead is alot easier then when you are sailing astern.
With SSE it's also smart to check out to which side the stern goes due to propwalk when you give a kick a stern. If for example, the stern goes to port with astern propulsion the best way is to dock portside. When you are almost alongside with still some speed ahead you can give a kick astern to get the speed out and to get alongside.
Manoeuvering isn't rocket science, you just need to practice alot and use your common sence. Try to predict what the vessel will do with every set up and figure out where the pivot point is of each vessel. Every vessel has their own do's and dont's