Here are the steps to clean aquarium sand:

1. Remove any visible debris from the sand with a small net or aquarium vacuum cleaner.
2. Rinse the sand in a bucket of lukewarm water until the water runs clear.
3. Place the sand back into the aquarium.
4. Repeat this process every two weeks or as needed.

If you have saltwater aquarium sand, it may require more frequent cleaning than freshwater sand.