The bedroom can be a tricky place when preparing to sell your home.  Aside from the kitchen and living rooms, most people spend a significant amount of time in this space.  In direct relationship with the amount of time spent there comes clutter, personal items (pictures, change, clothing, etc.) and an increasing challenge to make the room pop.Simply put, most people just have TOO MUCH STUFF in their bedrooms.  Selling your home is a good time to address the 300 pounds of clothing you haven't worn in years.  Aside from that - a few simple rules to follow:

1. Your closet doors should shut. Nothing looks worse (in pictures and in person) than a closet bursting at the hinges full of stuff.  The doors should shut and when opened one should see floor on the bottom, wall in the back and the ceiling above. 
2. Dress up your bed. Many times I suggest a new comforter (unless the one you have doesn't look worn and washed.  Clean up your headboard, all loose change, books etc. should be removed.  Think of it this way, your bed should look like the bed you see in a furniture store (they are trying to get you to imagine your stuff on the bed, which is what we're trying to do as well when selling your home).
3. Open your window. Natural light paints a room more than any other tool you can use.  I'd say over half the homes I sell have their blinds tightly drawn limiting the natural light entering the room.  I do it too, it's the cave mentality, we want to feel protected and secure in our bedroom; unfortunately it's not ideal when selling.
4. Make it smell good. Most of the time this means doing the laundry.  Other times it's a pet bed.  Overall - freshen up the items in the room that hold smells - these are: Bedding, Pillows, Carpet, Dog Beds, Clothing and garbage cans.  A small oil-stick scent can help, but you want to avoid making it look like you're covering something up.

The bedroom is one of the most important rooms in the home (aside from the kitchen) for a buyer's decision.  Optimizing this area will help your home sell faster and in many cases for more money.