Wash linen pants using a mild detergent on the gentle cycle of your washing machine. You may want to use cold water, but hot is OK for white pants. Wash dark pants with dark clothing and lighter-colored pants with lighter clothing. As always, avoid washing your white pants with brightly colored clothing -- unless you really want pastel-colored pants.
Dry the pants in the dryer on low or medium heat. You can also dry your pants outside, if it's sunny where you live. Avoid air-drying them in a damp area, such as a basement, because linen can mildew. You want pants that are crisp and clean, not moldy and moist.
Iron the pants using the hottest setting on a steam iron. Some people like the rumpled look of linen. If that's you, feel free to skip the ironing step. If you iron, do it while the pants are still a little bit wet to get the best steam and remove wrinkles easily. If they do dry completely, spritz the pants with some water while ironing. Don't worry if the pants don't completely smooth out or become crisp as you iron them. Go for the natural look.
Hang the pants after washing and ironing them to avoid creases.