Mix everything together in a big container with a lid (we use an old 1 gallon vinegar bottle), and shake. It may be a bit cloudy as the castille soap tends to clot up a bit, but it works very well. The tea tree oil and lavender oil are both natural disinfectants and good at fighting mold. The lavender also makes it smell nice in a natural way. You should be able to find castile soap, tea tree oil, and lavender oil in most health food stores (or online).
Pour some of the mixture into a spray bottle and use for all-purpose cleaning.