It's all too easy to carry around a permanent marker in a backpack only to find out later that the cap was off and you've been left with a nasty stain on the fabric. Don't worry, however, because permanent marker stains don't actually have to be permanent. You can significantly lighten and even completely remove permanent marker stains from a backpack if you treat them quickly and with the right method.
Empty the backpack of its contents.
Spray enough hairspray directly onto the stain to thoroughly dampen the area.
Press down on the stain with a clean, white cloth to blot out the hairspray and ink. Continue doing this until you don't see anymore marker ink transferring to the cloth.
Dab the area with another cloth that is wet with clean water.
Blot dry again.
Dab rubbing alcohol onto the stain if any marks remain.
Blot dry once more.