Objective: How to decorate a lamp shade colorfully?

Which of the following solutions is more sound in terms of naive physics reasoning?

Options: (a). Cut out material that is colorful and pick your color scheme, remove the lamp shade and paste the pieces onto the lamp shade as desired (b). Cut out the material that is colorful and pick your color scheme, turn on the lamp and glue the material onto the lamp shade and light bulb
(a).