I water when they are nearly dry and water until the water runs out the bottom of the container.

I suspect that is the watering method used by the majority of gardeners.

I doubt that you'll ever get all your plants onto the same schedule. Even the same variety in the same size pot will use water differently.

With some plants, melons for instance, you should actually shut off water as the fruits mature. This will concentrate sugars and prevent splitting. This is true for tomatoes as well.

Brook