To remove the Joey Baby Mattress cover, unzip the zipper, which can be found on the underneath side of the mattress. Pull off the cover and remove. Make sure you only remove the outer cover (as the inner water resistant cover is not designed to be removed).
You can wash the cover in your washing machine on a cold cycle with a mild detergent, then line dry in the shade. Please don't use any bleach, and do not tumble dry, iron, or dry clean the cover.
To refit the cover, place the top four corners on the top of the mattress and pull down, flip the mattress over and ensure the bottom 4 corners are over the bottom of the mattress. Close the zip, and secure the zipper puller under the tab, ensuring it is not exposed.