Measure the space where the bookshelf will go (height, width, depth)
Choose the bookshelf design (number of shelves, open vs. enclosed sides/back)
Select materials (plywood/boards, back panel, screws, wood glue, optional trim)
Decide on shelf spacing and thickness
Cut the wood to size (shelves, side panels, top/bottom, supports, back)
Sand all cut edges and faces
Mark shelf locations on the side panels using a square
Pre-drill holes for shelf supports and fasteners
Attach shelf supports (wood cleats, slotted rails, or shelf pins) to the side panels
Dry-fit all components to confirm alignment and squareness
Apply wood glue to mating surfaces
Fasten side panels to top and bottom using screws (and clamps if needed)
Install shelves onto supports (or fasten shelves directly if using fixed positions)
Attach the back panel (nails or screws; ensure it is square)
Add optional trim, corner blocks, or decorative trim pieces
Fill screw holes and gaps with wood filler
Sand the entire unit smooth
Finish with stain/paint and a protective topcoat (as desired)
Let the finish cure fully
Place the bookshelf in position
Secure the bookshelf to the wall with anti-tip brackets if it will be tall or loaded with books