Create a soap bubble solution by adding a bit of glycerin to a store-bought toy soap bubble bottle. The glycerin will make the bubbles last longer, and give you more time to photograph them.
Choose a bubble wand with a large diameter. Smaller soap bubbles are more mobile and float faster on air currents. Larger soap bubbles are more likely to hang in the air long enough for you to photograph.
Place a backdrop behind the area you intend to use to create the soap bubbles. Black backdrops will make the colors more vivid and vibrant, while colored or patterned backdrops will create reflective effects in the bubble.
Mount your camera on a tripod pointed directly at the space between the tripod and the backdrop where you intend to create your bubbles.
Attach a shutter release cable to your camera so that you can more quickly trip the shutter when the bubble is in view of your camera.
Set your camera to manual mode and adjust the aperture and shutter speed to the appropriate levels to expose a subject properly in your lighting conditions. You should use a fast shutter speed of at least 1/200th of a second to compensate for any bubble movement. Use burst mode--which will continue capturing images while the shutter button is depressed--if your camera supports it.
Attach a flash unit to your camera or use an off-camera flash to brightly illuminate your bubble. The bright light will be reflected in the vibrant rainbow of colors on the surface of the bubble.
Create a bubble in the field between your camera and the backdrop and depress your shutter release button. If you are using a burst mode, continue holding the shutter button down until the bubble moves out of the frame or pops.