Carpets that are near windows can fade in the sun over time. It is very costly to replace the carpet, and it isn't necessary if the carpet is in otherwise good condition. If this happens or you just want a different look for your room, you can dye the carpet to change its color. It's very inexpensive and takes a just little bit of your time.
Remove all the furniture from your room and vacuum the carpet really well. Use the hose attachment to get into all four corners and along the baseboards.
Use a carpet shampooer to clean your carpets the day before you decide to dye them. When you brush the dye in, you don't want to be brushing around dirt. If you don't want to shampoo the carpets yourself, you can hire someone to do it.
Use painter's tape around the edges of the baseboards where they meet the carpet. This will protect them from the dye.
Purchase some carpet dye (see Resources). Choose a dye that is a darker color than the carpet that you already have. If it is lighter, it may not work.
Mix the dye in a bucket with some water. The dye is a concentrate, so you will have to measure and add the amount of water that is indicated in the product's instruction label.
Start at the farthest end of your room and work your way out. This way you won't trap yourself in and end up getting dye all over your feet. Use your brush to apply the dye to the carpet. Keep working at it by moving the brush around in a circular motion. Don't move onto the next spot until the spot you are working on is finished.
Give the carpet a day or two to dry. If you want the carpet darker, apply a second coat after the first coat has dried.