It's super easy.
- Set your camera to Aperture Priority. (This is A on a nikon and Av on a canon).
- Adjust your aperture as wide open as it will go (this means the smallest number). (I used my 35mm lens at f1.8).
- Turn your ISO as low as you can. (I used 100 ISO).
- Let your camera figure out shutter speed : )
- Ok, ready, now you want to focus on something in front of the lights. The farther away your focus is from your lights, the bigger the bokeh will be.
Here I focused on a little star shaped card holder:
Here I focused on my finger just right in front of the camera then moved my finger before taking the picture. Genius, I know, I know...
Seriously, anybody could do this, as long as you can manually adjust your aperture, but it looks really difficult.
PS. Before you go have you entered the awesome giveaway I have going on right now?