One really good tip that I learned when I was student teaching years ago is to use a plastic ice cube tray with multiple wells for diluting watercolors and washing brushes when changing colors. No more muddy brown water jar to knock over. Refill your ice cube tray only when you run out of clean wells and rinse out when you are done using it. I use it for water colors and acrylics. Don’t worry about the acrylic stains on the plastic. They won’t affect your water and they add ambiance and character to your water tray.