Some people let friends and family write encouraging words on their hand casts with a marker, but this sometimes results in inappropriate messages that need to be removed. When that's the case, it's important to clean your cast carefully to avoid weakening it. You can erase unwelcome marker messages with common household solvents, and then dry the cast as thoroughly as possible.
Blot rubbing alcohol on the marker stain. Work from the edges of the marker stain toward the center.
Rub gently until the marker stain is gone. Use as much rubbing alcohol as necessary, but don't saturate the cast as this can weaken it.
Sprinkle baking soda over the marker stain if it is still visible.
Rub the baking soda into the marker stain with a scrubbing brush to remove the stain completely.
Wipe the cast with a water-dampened cloth.
Dry the cast completely with a hairdryer on low heat.