I usually do 4,5,2,1... But someone else may have a better suggestion. Unlike a lot of characters, you don't want to cut the 2, 4, or 5 skills early, because the heal comes at the end of the skill (unless your HP is full). If your HP is full, you can cuts those skills early and add 3 to the rotation.
Use the 4th skill to "entice" world bosses. It makes them walk towards you and stop attacking.