Obtain the "mike" ability and find any of the secret switches used to open up more areas. Use the ability two times first and then use the third time on the secret switch. You must jump from above and be very close to the switch as you use the mike. If the glitch worked correctly, when it shows what item you have, it should display "00" for item usage and you can use the ability an additional 266 times. If it failed, then you either did it too early or hit the switch before you used the ability.