Deflate board and remove your valve cap.
Open your orange patch kit and take out the valve wrench.
Insert the valve wrench into the valve assembly and tighten by turning clockwise. The trick is to put lots of pressure on the head of the wrench while tightening.
Warning: Do this while board is deflated! If you turn the wrong way, the valve assembly will shoot out of the board and cause injury.
Replace the valve cap and re-inflate your board. Check for hissing. If the valve is still leaking, complete the "Valve Maintenance" procedure under "Support."
(Note: Never use a screwdriver to tighten the actual valve at the center of the valve assembly)