Here is a series of shots that required a little more brainstorming, planning, anticipation, cooperation, measurement, trial and error, improvisation, and luck than usual (even more so than the food photography attempt the week prior which was for another contest).
Anyway, several simple techniques were employed for taking these shots.
First and foremost, there was the usual bokeh filter.
Since the gaps in the gear design wouldn't work with the typical cardboard cutouts, I used sticker paper on an old UV filter instead. A clear sheet of plastic might have worked, but I opted for glass since I figured that plastic would decrease image sharpness even further.
Note that using an excessively large cutout may mean that the outer parts of the design would not be included in the resulting bokeh. Based on my measurements, the largest diameter I could use for the EF-S 55-250mm lens was approximately 2.5 centimeters.
The second requirement was flash. On-camera flash was was an option, but the extra power of an external flash unit was more ideal for balancing flash and ambient light.
Aside from the silicone jacket on the camera, and the lens was covered with a rolled-up magazine to act as lens hood for reducing flare and to serve as protection.
Not really a necessity, but a remote trigger can be handy if you insist on using relatively slow shutter speeds for multiple flash exposures.
The final element was having bubbles floating against the night sky. I had already done this before, but my setup was simpler back then (on-camera flash only, wider telephoto at only 135mm, no custom bokeh design).
I chose bubbles because they were the only reflective objects that I knew of which didn't require suspension or any kind of physical support. Although the randomness of trajectory makes bubbles difficult to work with, I liked the limitless variety it offered. No two shots are ever the same.
Bubbles were also the reason for certain precautions which were taken, specifically the silicone and magazine covers (electronics and soapy water seem to be a bad combination) and the use of a UV filter instead of a plastic sheet (easier cleanup).
Incidentally, here is a clear shot of the moon which was taken using the same lens, but without the bokeh cover in the way.
Unfortunately, loss of image sharpness is the inevitable consequence of using an irregular design for the custom bokeh.
Credit goes to Jesus Ramon Ronquillo for lending me his EF-S 55-250mm lens for the weekend. These shots would not have been possible without his help.