If the snake is not losing all its skin at one time then it suggests that your humidity in your cage is not quite high enough. You could try to increase cage humidity, or you could provide a moist hide within the cage. This might avoid future shedding issues.
A common suggestion that is made when snakes don't shed fully is to let them slide through a damp towel, to rub off the remaining skin. Other people put them in a tub with damp paper towels.
It sounds as if you are making sure that the snake always does completely shed which is good, since skin left on can cause future problems.