Measure the wall space and decide the shelf dimensions
Choose the shelf material, such as solid wood, plywood, or MDF
Cut the shelf boards to size
Sand all surfaces and edges smooth
Mark the stud locations on the wall
Use a level to mark the shelf height
Install a hidden shelf bracket or metal support system into the studs
Drill pilot holes for the bracket or support hardware
Secure the bracket firmly to the wall
Drill matching holes or a channel into the shelf to fit the support
Test-fit the shelf on the bracket
Adjust the fit if needed
Apply wood glue if desired
Slide the shelf onto the support hardware
Check that the shelf is level
Secure the shelf with screws if the system requires it
Fill any visible holes or gaps
Stain, paint, or seal the shelf as desired
Let the finish dry completely before loading the shelf
Place items on the shelf within the weight limit