Cleaning your tent is not necessary unless it has an offensive odor or becomes heavily soiled. If heavily soiled, the pressure from a regular garden hose will remove most loose dirt. For more severe cleaning, set up your tent and hand wash it with warm water, a sponge and mild, non-detergent soap.
Do not use dishwashing liquid, detergent, bleach, pre-soaking solutions, or spot removers. Rinse well. It's important to remember that ultralight fabrics have a very thin layer of waterproof coating - you'll not want to be too harsh with it. If you're looking for tent safe cleaning and restoration products we recommend Gear Aid and Nikwax. Both brands make excellent products.
Dry your tent by pitching it or line-drying it. Never dry clean, machine- wash or machine-dry your tent. Any of these methods can remove all the waterproof coatings from the tent.