Use the pre-drilled hole on the top panel (A panel) to screw the strap in.
Secure the other end of the strap to a wall stud to prevent the unit from tipping over.
Place them at your desired levels inside the pre-drilled holes. For standard spacing, you might count three or four holes from a fixed point to ensure they are even. : Identify the two adjustable shelves (E panels).
: Useful for tapping in the back panel nails or shelf pins.
For more visual assistance, you can watch the Mainstays 3-Shelf Bookcase Guided Assembly or the Mainstays 5-Shelf Bookcase Guided Assembly for similar construction methods. Mainstays 3-Shelf Bookcase Guided Assembly
While most Mainstays units include basic hardware, having these on hand will make the process easier: : For the main structural screws.