Often times, there are certain shots that are considered bucket list. In short they are not easy to capture, and if you are lucky enough it's an addictive feeling.
There are a million lighting shots out there and tools exist to help photographers capture those shots. However try doing it free hand, Just you a camera and a tripod. No lighting triggers, no cable release, just you and your basic equipment.
That is how I shot this. Here was my formula. I used mirror lockup, ISO 100 and a 15 second exposure. My lens was a 24 to 105, and used a 10 stop ND filter, to cut out as much light as I could. My delay on my shutter was 2 seconds. There is no way to time the strikes, so I simply was patient and hoped that sooner or later I would be exposing a frame and get lucky.
Some will call it luck, I will call it faith and experience.
Hope you enjoy the shot as much as I did capturing it.