Vacuum the carpet thoroughly with the vacuum on its highest setting. Make sure that any loose objects are picked up off the floor and that dirt and dust hiding in corners is removed.
Spray the carpet with the carpet pre-treating spray, concentrating especially on areas with staining or heavy dirt.
Fill the carpet shampooer with hot water, according to the machine's instructions.
Follow the instructions that came with the machine and clean the carpet from corner to corner accordingly. Be sure to move gently across the surface of the carpet to avoid stretching or pulling it out of shape.
Use the water-extracting tool on the carpet shampooer after the washing is finished.
Test the carpet with your hand. If the carpet is more than slightly damp, and water droplets cling to your hands, use the water-extracting tool again.
Ventilate the room with open windows and fans, and allow the carpet to dry overnight before stepping on it.
Lift furniture or heavy objects when moving them instead of dragging them across the floor. Dragging these objects can cause serious carpet stretching damage.
Check to make sure that the padding underneath your carpet isn't too thick. Improper padding can lead to wrinkling or waving in the fabric of the carpet.