Take the frame of the daybed off the feet and place it onto a flat surface.
Measure the length and width of the frame, and cut out a piece of 2-inch thick foam sheeting using the same measurements.
Cut out a piece of 2-inch thick cotton batting using the same measurements as the frame.
Cut out a piece of upholstery fabric. Use the same measurements as the daybed frame, adding on 4 inches along each edge.
Lay the foam piece onto the daybed frame, followed by the cotton batting piece and finally the upholstery fabric piece. Position the fabric piece evenly over the frame.
Turn the ends of the upholstery fabric underneath the frame, then staple the fabric under the bed using a staple gun with 1/2-inch long staples. Keep the fabric taut as you staple.
Sew smooth-top buttons over the top of the upholstered daybed, spacing each button 6 inches apart. Insert an upholstery needle threaded with upholstery thread into the button hole, through the fabric, batting and foam, then back out through — next to the area where you inserted the needle. Pull tight to cinch the materials and knot the thread in place. Repeat with each button to create a tufted surface.
Place the tufted, upholstered daybed back onto the feet.