If sunlight hits the developing head of cauliflower, it will turn brown instead of creamy white. White is more appetizing. Prevent the light from reaching the head by following this procedure. When the developing head of cauliflower is about the size of a quarter take a rubber band and pull several of the larger leaves together and secure. This shades the head and keeps it white.
Every few days check on the head and harvest when ready by cutting it off the plant.
Enjoy the fruits of your labor.