Assemble a minimum of two different Christmas cactus plants, ideally of different colors.
Recognize the plants' reproductive parts. For Schlumbergera x buckleyi, or Christmas cactus, the stigma is crimson in color and protrudes from the plant. The anther is a small lump of yellow -- pollen -- that hangs from the filament, a long, white tubular shape.
Look for particularly receptive stigmas. Some plants' stigmas open into a star shape, indicating that their ovaries are ripe.
Stroke the anthers of one flower onto another flower's stigma. You may do this on flowers that bloom from the same plant, or you can choose completely separate plants. Rubbing anthers to stigmas transfers the pollen, which instigates the reproductive process.