Pets are more susceptible to heat stroke than humans, so take some basic precautions and keep them cool.
The most important tip is to never ever leave your pet in a car on a hot day. Even on a moderately warm day the sun can heat up the inside of your car to more than 110 to 120 degrees. You can't just crack a window and expect your pet will be okay. Take him out of the car and along with you on your errands, or leave him at home in an air conditioned room.
For longhaired pets, trim away excessive fur. It may look silly, but your pets will thank you if you get rid of the blanket of hair trapping the summer heat to their bodies. Don't shave them bald though. Leave enough hair to prevent sunburn.
If you leave your pets outside during the day, set up a shaded area for them to use for resting. If you don't have any trees or other plants to provide shade, invest in a doghouse. Never leave your pets tied up while you're gone. If they tangle themselves up in the leash, they could cut off their access to water and shade.
For indoor pets, walk them when it is cooler outside – in the early morning or evening hours after the sun has set. You'll both be more comfortable. When you leave for the day, keep the air conditioning blowing or open some windows and leave a fan running. Make the house as comfortable as you would want it to be if you were at home.
Fill your pet's bowl with fresh, cold water often. If it's outside, leave it in the shade. Make sure to use a heavy water bowl that cannot tip over. Put ice cubes in the bowl if you'll be gone for awhile to keep the water cool while you're away.
If you bring your pet hiking, bring water for yourself and for your furry friend. Collapsible water bowls are compact and easy to find at any outdoor sporting goods store. When you take a break to hydrate, give your pet some water too. If you bring your pet camping, don't leave him in a closed-up tent. It can be just as deadly as leaving him in a car.
Take it easy on your pets in the summer sun. Don't overdo it. They are just as susceptible, if not more susceptible, than humans to suffer from heat stroke and sunburn.