Harvesting: pick mushrooms just before the veils underneath the caps break. Twist and pull gently from the base. Don't wait too long, once spores release, the kit stops producing.
Drying: lay them out on kitchen towels in a dry spot, not touching each other. No direct sunlight, no oven, no microwave. Room temperature, good airflow. Takes a few days until they're cracker-dry.
Storing: fresh mushrooms keep 5-10 days in the fridge. Dried mushrooms keep for at least a year in an airtight container in a cool, dark place.