Improper washing can cause a lot of pilling to occur. It is suggested that you use less detergent when washing your sheets and that you select as short and gentle a cycle as possible. Another strong suggestion is to add vinegar to your wash as it aids in protecting and cleaning your sheets. Avoid fabric softeners but dry using a slow and gentle tumble. Always carefully measure out the detergent according to how large of a load you are going to be washing. If your washing machine does not have a gentle setting then you might want to wash your sheets by hand. You can do this by soaking them in a large bucket with a mixture of detergent and water. Then take it out and rinse your sheets to remove all of the detergent. You can then hang dry your sheets outside.
Razor & Scissors
Both small scissors as well as a safety or disposable razor can be used to remove pilling. Stretch out the fabric as well as you can and carefully shave or cut of all pilling. Be careful not to cut the sheets or pillow cases. You might want to get some help by a friend or family member to hold the sheets tightly while you cut or shave the pilling. Always be careful when handling a razor as they are extremely sharp and can easily cut your fingers or sheets.
Battery Operated Shaver
Many drug stores, pharmacies and grocery stores carry specialized small shavers that are created specifically for removing lint and pilling from fabric. Stretch areas of fabric out and gently run the shaver over the area. These cloth shavers are relatively inexpensive but do their job quite well. You will have to make sure that the cloth shaver you buy is designed for your needs.
Once you have removed all the pilling that you can, wash and dry the sheets once again using the methods suggested in Step 1. Remember it is entirely up to you if you want to wash your sheets in the washing machine or by hand. The whole point is to effectively remove the pilling off your sheets.