Summer is the time of long hot days, so you should remember that dogs cannot cool themselves by sweating like humans. The main way a dog cools off is by panting but this is enough when it is extremely hot and humid.
Here are some ways to keep your dog col and comfortable in the summer.
Most important is to keep fresh, cool water available to your dog at all times. Make sure that water dish is in a shady location. Some crushed ice in the water might help too.
In case that dog is outside, shelter from the sun is very important. Dog house should be large, insulated and well ventilated and it is best if it is placed in a shady area.
If your dog loves water, then a large tub or kiddie pool might be a good idea. Make sure you supervise your dog at all times, keep the pool in a shady spot and change the water frequently.
When it is very hot, your dog will do best indoors. Basement is usually the coldest place in the house so if it is comfortable enough, that is a good place for your dog. You can also use a fan or air conditioner.
If you are taking your dog outside, try to do it early in the day before the heat makes exercise too dangerous.
And if you are using a car, never leave your dog there on a warm day! Cars will heat up very quickly even if windows are partially open or car is in the shade and your dog can show signs of heat stroke in a matter of minutes!