This tutorial provided by the Michigan State University Extension . Or you may find it more convenient to have it done professionally each time special cleaning is needed, rather than doing it yourself. Professional cleaners use similar methods to home cleaning, but they should have the knowledge, equipment and experience necessary to do a more thorough job of removing embedded soil.
Professional cleaners can also handle spot removal, re-dyeing, rebinding and repairs.
Always alert the cleaner to the location and cause, if known, of spots and stains that require attention. When selecting a cleaning service, the main factor to consider is the operator's skill and ability. Ask reputable carpet dealers in your area whom they recommend. Satisfied customers may also suggest a cleaner to contact. Rug cleaners of longstanding reputation can usually be relied upon to provide satisfactory service.