Check hose connections for leaks and repair them quickly. Even a tiny leak can translate into thousands of gallons of wasted water over a short period of time.
Adjust your sprinklers so water is aimed directly at plants rather than sidewalks, paths, driveways or fences. Use sprinklers that emit large droplets rather than a fine mist, again to reduce losses due to evaporation.
On automatic sprinkler systems, install a moisture sensor. This is a probe placed in the ground that determines when the soil needs water and then turns on the sprinkler. This is probably one of the smartest water-saving devices ever invented. It can save you tons of water and money.
Install drip irrigation systems and soaker hoses in flower and vegetable gardens, around trees and shrubs, even in containers.