Steps:
1. Remove the shower valve handle.
2. Unscrew the cover plates from the shower valve.
3. While standing in the shower, drill ¼-inch holes through the wall behind the shower valve.
4. Cut open the wall behind the shower valve using a drywall saw.
5. Cut a 1x4 to fit behind the water pipes.
6. Screw the 1x4 to the studs on either side of the shower valve.
7. Secure the water pipes to the 1x4 blocking with copper clips.
8. Cover the hole cut in the back wall with a plastic access panel.
9. Apply silicone caulk to the backside of the wall plate, and screw it in place.
10. Place a bead of plumber's putty around the valve cover and reattach it.
11. Replace shower valve handle and remove excess putty from around the valve cover.
