Lay the canvas bag down flat. Use the paint brush to brush the white paint onto your child's hand. Don't paint their thumb - you only want the 4 fingers for this craft. (We found that handprint crafts turn out a little better/"cleaner" when we painted our daughter's hand than when she dipped her hand directly into the paint).
Help them carefully lay and press their hand onto the bag and then pull straight back up so the handprint doesn't smear.
To get a smoother ghost, go back over the handprint with the paint brush (and more white paint if necessary)
When the ghost has dried, use black paint to add a face to your ghost.
Use the glow-in-the-dark paint to outline the ghost and to write "BOO!" onto the bag. **Note: although you are painting on fabric, regular white craft paint is ok for this craft assuming it will most likely only be used on trick-or-treat night and won't be washed. If you think your craft will get more use, please use fabric paint instead so that the bag holds up better.