Washing all your seeds at once will cause some to sprout before you are ready to use them. Only wash the seeds you plan to immediately sprout.
Place the tray and pan in a dark room to allow the seeds to sprout. This method works because the clay tray will absorb water from the pan - just enough to moisten the seeds enough to help them grow. With this method, no rinsing is required.
Sprouts are also great as a filling for sandwiches. Sprouts are tasty inside a pita wrap. Try adding nutrition to your standard burrito by wrapping some sprouts in with the beans and rice.