Using the straight edge, center the acetate sheet on the middle of the visor’s interior. Tape the acetate sheet to the inside front edge of the visor, allowing it to hang down. Pull the side of the acetate sheet to the side of the visor, allowing it to follow the curve. Use a small piece of packing tape to secure the acetate sheet in place. Repeat for the other side.
Add additional pieces of packing tape along the seam between the visor and acetate sheet as needed. Wear the visor as you would normally.
Templates referenced above follow similar medical materials that are recommended for these items. Medical professionals receiving these items will decide how best to use them.