Clean the rush weaving with a damp cloth. Carefully remove dust and dirt from the weave without damaging it. Let it dry completely.
Place the chair seat on a drop cloth in a well ventilated area. Tape off any areas of the chair that you do not want coated with shellac.
Stir the shellac with a paint stick. The shellac should mix with the alcohol that is in the can. Pour the shellac into a small tray or can.
Apply a layer of shellac to the rush weaving with a paintbrush. Cover the weaving and then let it dry per manufacturer directions. Repeat with a second coat of shellac. Let the shellac dry for several days before use.