Mix the clean sand, perlite and cactus compost in equal amounts to make a growing medium, and put an even layer of the mixture at least 1 1/2 inches deep in the seed pan or small pot.
Plant the jade seeds in the growing medium. Some varieties of jade have larger seeds than others. Bury the small seeds around 1/2 inch deep in the growing medium, and bury large seeds around 1 inch deep in the medium. Water gently, but enough to soak the growing medium and seeds.
Place the planted seed pan or small pot in full sunlight. It is important to maintain a high level of humidity near the seeds. If you do not have a humid greenhouse, you can place the seed pan or pot in a transparent plastic bag, or spray or mist water once or twice a day. The seeds should germinate within a week.
Transplant the seeds as soon as a few days after germination. Jade plants do develop relatively extensive root systems, so it is a good idea to transplant into a larger pot if you plan to keep the plant for a few years. Jade plants grow fast in warm, relatively humid environments, but will still do well indoors if given plenty of light and only watered after their soil is completely dry.