To prevent creases, wash permanent-press garments in warm water and rinse in cold water. Place a dry towel with the wet clothes in a half-filled tumble dryer. Hang or fold the clothes once dry.
Ideally, permanent press garments should be hand washed and allowed to drip-dry in the garden or over a bath, hanging from a rustproof hanger.
You may not have to iron creases caused by sitting. Go over the crease in your trousers or skirt with a flannel or sponge moistened in warm water, and then hang the garment up to dry.