Before starting you should ensure that the lens is fully closed. If not, you can close it by applying 3V from 2 AA or AAA alkaline cells to the zoom motor as shown. Apply positive to the terminal nearest the lens barrel to close it, or the other way round to open it. For a sticky lens you can use up to 5V, for example from a USB charger.

The lens cover should now be fully closed. (It needs to be fully closed otherwise reassembly will be very difficult if not impossible.) Tape it shut, but make sure you use tape that can be easily removed without bending the lens cover blades.