Things You'll Need
Instructions
Cut a piece of cardboard into a 7-by-5-inch rectangle. Cut another rectangle out of the center of the first rectangle that is 6-by-4 inches, leaving a frame of cardboard.
Cut a piece of cardboard into an 8-by-3-inch isosceles trapezoid. Make the trapezoid 7 inches tall. Cut out a second trapezoid with the same measurements.
Lay the rectangle flat with one trapezoid on each side. Touch both of the 8-inch sides of the trapezoids to both of the 7-inch sides of the rectangle. Tape each trapezoid at the connection using masking tape and centered on the sides of the rectangle. This leaves 1/2-inch of excess on each side of the trapezoids.
Cut a piece of cardboard into a 6-by-3-inch trapezoid. Make it 7 inches tall. Repeat with a second piece of cardboard. Tape the trapezoids at the base to the remaining sides of the cardboard rectangle, once again leaving 1/2-inch of excess on each side of the trapezoids.
Cut a piece of white silk into a 7-by-5-inch rectangle. Glue this over the cardboard rectangle, covering the masking tape and the hole in the rectangle frame.
Leave the softbox flat and tape 1/2-inch hook-and-loop tape strips to the excess flaps on the sides of each trapezoid. Place the rough, or hook, sides of the hook-and-loop tape on the small trapezoids. Tape the soft, or loop, sides of the hook-and-loop tape on the large trapezoids.
Flip the softbox over and fold the hook-and-loop tape flaps back 90 degrees. Fold the cardboard trapezoids back 90 degrees.
Place the softbox over your flash head and fasten the sides of the hook-and-loop tape together as tight as necessary to hold the box onto your flash. This forms a pyramid-shaped box with the small end open. If the opening is too large for your flash, tighten just the ends of tape until the box is secure.