Sow the seeds directly in the garden as soon as the soil can be made fine and loose. Plant them every 6 inches, covering them firmly with soil.
Lettuce needs plenty of moisture. Water regularly to keep the soil from drying out; however, overwatering or lack of air circulation will cause the leaves to rot.
As the plants begin to crowd, pick individual leaves regularly to eat. For the best flavor, pick them young. Harvest a few leaves at a time to continue growth, or harvest the entire plant.