Lay your 1-by-4-inch board flat and horizontal. Draw a line across the board that is parallel with the 12-inch edge and 1-inch away from one of the edges. Draw one more line that is parallel with the 12-inch edge, and 1 inch away from the first line, and 2 inches away from the same 12-inch edge.
Draw 10 lines that are perpendicular to the first two. Space them 1 inch apart so the two outside lines are 1 inch away from the ends of the board. Drill an 3/8-inch hole where each line intersects. Erase the remaining pencil marks.
Use your stud finder to located studs in the wall where you would like to hang your screwdriver holder. Position the 2-by-2-inch board horizontally on the wall so its 6-inch center is over the stud. Use your level to ensure the board is truly horizontal. Screw two 4-inch screws through the board and into the stud.
Position the 1-by-4-inch board on top of the other board so the ends are flush. The holes should not be covered underneath by the 2-by-2-inch board. Screw through the 1-by-4-inch board and into the board that is attached to the wall. Use four 2-inch screws that are spaced 3 inches apart.