Cropped from a wide angle 8 second exposure. This was taken at the end of the storm. The tornado sirens kept us in the basement when it was really lightning up.
My method, your results may vary: set camera on tripod under cover of garage, wide angle lens in general direction of lightning, full manual operation of camera, manual focus on infinity, ISO 100, 8 sec exposure (fastest for SD card write in my camera, 10+ seconds took too long between shots) with f/8 or f/9 (depends on shutter speed and sky lightness; I try to get a dark image when there is no lightning in the frame). Press shutter, when done, press shutter again, and again, and again (as long as lightning is in the area). Out of 120 photos, 7 had lighting; this was the best and still needed a crop. The wide angle worked best for me as it more likely captured the entire lightning bolt.
Of course luck plays a role in it too!
Yay, made it to the front page of Explore and as high as #2.