Before you start, make sure the batteries are in your vibrator. With the Exacto knife, cut a small slit long ways across the top of the foam index finger. Cut straight down into the foam to form a pocket large enough to accommodate your vibrator.
Insert the vibrator into the hole, base first. The foam should be flexible enough to allow you to turn the vibe on and off once it is inserted, but if not, turn it on before you put it in.
Put on the foam hand and give yourself or someone else the finger.