Take a sample of your wood color to a home interior or home improvement store. If you do not have a sample of the finish, take a photo of the floor with you.
Look at rugs that fit the decorating style of your room. For example, do not choose a modern rug for a colonial themed room; it may stand out and clash.
Look for colors that will complement the colors in your room besides the floor color. Consider matching the rug with the wall or trim color to bring the whole room together.
Choose a level of detail in your rug. If you want the rug to be the main focus of the room, choose a busy and detailed design. If you want the rug to be muted, choose a solid color with an interesting texture.
Choose the size of your rug based on both the size of the room and the purpose. If the rug is for a doorway, you'll obviously want to opt for a small rug. If you have your couch or dining set on it you should choose a rug that is much larger.