Dec 24, 2009 · Use 2x4 boards to create a floor frame. Put two 2x4 boards the entire length of the wall on both sides of the frame. Using your measuring e and pencil, mark both 2x4s every 14 inches. Add the remaining 2x4s by laying them on the marks you made and secure each board using framing nails and a hammer. Step 6: Secure the Floor Frame