Water from the dryer (the container) put it back in the washing machine (saves water).
If you do not have kitchen boiler and the hot water to come out of the attic, it can take a long time before the water is warm, with a lot of water wastage due. Catch this "first" water in eg. A watering can or coffee / tea (which is often already on the counter and used daily word!) Until the hot water has reached bottom. So you can use this water later for coffee / tea or watering the plants.