You've spent a lot of time and effort to create the perfect design for your products - it's important that you and your customers know how to take care of them in the best way possible!
These should be only washed with like colors. You can certainly machine wash the garments in warm water that is around 104°F/40°C. Keep in mind that you should only use non-chlorine bleach if necessary and do not iron the decorated (printed) areas. If the garments require dry-cleaning, you can use any solvent except the trichloroethylene. Tumble-dry these garments on medium.
The pillowcase itself can be machine washed according to the above mentioned care instructions. However, the pillow instert should only be handwashed.