This post specifically addresses the Fray Issue that has come up when sewing the MasksNow Pleated Pocket Mask. Troubleshooting for this issue is going to vary based on fabric thickness.
The leading edge of the pocket in the original instructions is not hemmed at the pocket opening and this can cause issues of fray especially in washing thick fabrics.
Hem the double-folded edge at the beginning of the assembly between Step 1 and Step 2. This is what it would look like:
Hem the single-folded edge and nose wire pocket in one go at the beginning of the assembly between during Step 2. This is what it would look like:
Hem the single-folded edge with a zigzag stitch at the end of Step 1. This is a good solution for thick fabric.
Whipstitch the frayed edge. This is a good solution for masks that are already complete and that frayed in the wash. There are tons of hand sewing whipstitch edges tutorials on google. They will all work.
Glue… fabric. Depending on how bad the fraying is products like Fray-Check and other washable fabric glues can also be used. But I recommend this solution for the end-user only as you never know what folks are allergic to.