Mulch your landscape beds. This will help  to save water, slow  weed growth and keep soil cooler. Spread 1-3 inches  of hardwood mulch or other organic material under shrubs trees, annuals and vegetables.  
Other benefits of mulching :

Conserve moisture - allows for deep and infrequent watering thus saving water and helping to avoid  drying out of the plants.

Subdue weed growth
Eliminate stress in shallow-rooted plants
Keep soil temperatures more stable,  warmer in the winter and cooler in the summer.
Mulching can protect root damage, leading to stress on your plants.
Creates an environment  that promotes  numerous beneficial organisms that fight pests in the garden  Earthworms thrive in cool damp soils creating a much healthier soil.
Provide nutrients to the soil and to plants
Improve soil structure and drainage
Can provide  bark in a bed of landscape shrubs

There are several things everyone can do indoors to prepare for the warmer season.  Put your catalog orders in now...