The key to any successful organization project is categorizing. By grouping like things together you will make them easy to find for future use, easy to remember when it is time to put them away and your closet will look nice and orderly. Proper storage containers will make this task easy to accomplish and maintain.
Baskets, bins, and drawers are the perfect addition to any closet. They can be used to store socks in one, belts in other, just try to keep like things together. Additionally, you will want to categorize your hanging clothing. The most popular way of doing this is to put all of your pants in one area, shirts, in the next and so on. If you want to go further when you are categorizing, separate your clothing into groups of when you would wear them (to work, to the gym, at home, at night) and then group the pants and tops together within those smaller categories.
Hooks are another way to store like things together. They can be used for belts, ties, or purses. Having these smaller accessories in one place and on display will make your choices in the morning quicker. If you have a larger closet, you may want to keep your jewelry in the closet too. You can use a traditional jewelry box to keep them together or a small box for your earrings and another for your necklaces and so on.
You can think outside the box too, brainstorm how you use the different items in your closet. Maybe your workout gear can be stored in ready to wear bundles. Take your pants roll up a shirt and socks inside and they are neat inside your closet and ready to grab when it is time to go to the gym for a work out.