Using mulch on the garden will keep soil cooler and reduce evaporation,
so you won't have to water the garden as often.
Research your plants, some actually thrive in drier conditions and will not benefit from over watering.
Install a water tank in the garden to collect the rainwater. This will mean you always have water to use for watering the garden without the need to use fresh water from the hose.
Minimise lawn areas and plant water-efficient native trees and plants.
Use drought-resistant grass for lawns.
Design your paths to direct water runoff to the garden beds.
Create more shade and shelter in your garden. This will reduce heat and provide more wind protection which will help save water.
Water in the early morning or late afternoon. This will help reduce evaporation.