1. Fill a large bowl with cold water and gently put in the leaves.
2. Stir them around gently and then let them sit a couple of minutes. Transfer them to another bowl.
3. Feel the bottom of the first bowl. If you feel any sand or grit, rinse it out, refill the bowl, and repeat the soaking.
4. Most lettuce requires only one soaking, but some greens, such as arugula or basil, are sandy and require as many as three soakings.