During reassembly, follow these instructions to reinstall your vibrator:

Peel off the vibrator adhesive from its liner and apply the sticky end to the bottom of the vibrator.

Use tweezers, or your fingers, to pull up on the white liner to expose the top layer of adhesive.

Insert the vibrator and apply pressure to adhere it to the frame.

The adhesive is very thin and hard to distinguish from the liner. Use your fingers to check if the adhesive transferred correctly.