Step 6: Add Sand and Rocks
Add your sand and as many "Rocks" as you like.
Start raking it and feel soothed.
When you're done, put the rake in the cubby (if you made it) with any extra rocks and leave it on your desk to impress.
Also, a variant of this would be to make a Zen Snack Garden. I got the idea when I couldn't find sand (sanitize, fill with sugar, add some chocolate covered raisins or peanuts... or whatever tasty snack you like!)