Hydrozoning
Group planting by water need and place the highest-need zone where it is seen most. The further from the house, the tougher the planting should be.
Soil and mulch do the saving
Organic matter increases how much water soil holds; a thick mulch layer stops it evaporating. Together they cut irrigation demand more than any controller setting.
Shrink the lawn, don't delete it
A smaller, well-shaped lawn used as a green room costs far less water than wall-to-wall grass, and still gives the softness a garden needs.