How much time do you spend sorting your piles of dirty laundry before they go into the washer? Any time is too much time. Eliminate sorting as a laundry task altogether by having multiple hampers or laundry baskets in every bedroom. The categories you use to divide up laundry determine the number of baskets you'll need. The general rule is to sort into three categories -- whites, colors and delicates -- but you can organize your baskets by wash method, type of fabric or whatever other categories you like to sort by. When you get undressed just toss your garments into the correct basket, so when you grab a basket on laundry day you'll know it's already sorted and ready to go.
If you have a large family, rather than having individual hampers in every bedroom, put them in a hall or common area so you don't have to gather up laundry from all over the house.