Do you have one of the new, foaming hand soap dispensers from Dial, Bath & Body Works or one of the other numerous makers? If so, you can save money on the refills by making them yourself. Foaming hand soap is easy to make and even easier on the wallet. Mix up a batch, and see what I mean.
More Frugal How-To's:
Wouldn’t the soap to water ratio sort of depend on how large the original dispenser is? How can “1 tablespoon” work for all container sizes?
You probably already have this down by now, 6 to 1 ratio works well for us.
Does it matter what kind of water you use? Can you use regular tap water?