Choose a tray for your desk top Zen garden. You can use metal or wood, but the tray must be shallow and small enough to fit comfortably on your desk. A wooden serving tray works well.
Fill the tray with white sand to ½ inch of the top. The sand is symbolic of water. Purchase deluxe playground sand, which workers screen and filter to remove debris.
Add some decorative rocks to the garden to symbolize mountains. Go with odd numbers rather than even number for the most visually pleasing display.
Keep at least one miniature rake beside the garden. You can find these in a hobby store that sells miniature collectibles. You can use the rakes to create ripples in the sand that mimic water ripples.
Replace the rocks or choose a different color of sand as it suits your mood. Flow and change are Zen concepts and your garden shouldn't feel stagnant.
Maintain your desk top Zen garden. Wash the dust off the rocks once a month, and change the sand twice a year to prevent dust buildup.