If the product comes with care instructions, please follow those recommendations. If the item doesn't come with specific care instructions, you can follow general rules of care. We found two articles that are helpful.
Outdoor cushions & pillows:
https://www.bhg.com/home-improvement/porch/outdoor-rooms/how-to-clean-outdoor-cushions/
Outdoor furniture:
https://www.marthastewart.com/8302510/how-to-clean-care-for-outdoor-furniture