It takes lots of patience and a camera with a bulb setting. Try using an all manual camera and load it with 400 film and set the aperature to about f/8. Use a wide angle lense and point the camera in the general vicinity of the lightning and leave it open for several bursts of lightning, then advance to the next frame. Wait until the lightning is within 20 miles or so from you, no less or it will be dull on the pics. On the other hand, don't let it get too close! Good luck keep trying!