Firstly, stay calm, and try to keep your dog calm, too. If they have an open wound, clean it with fresh, warm water, and cover it with a clean damp cloth. If they are losing a lot of blood, apply pressure to the wound. Unless they have a heat stroke, cover them with a blanket, and restrict their movement. Safely put them in a dog carrier or a stretcher, and take them to a vet immediately.
The following items are essential in a first aid kit for dogs:
If your dog is seriously injured, they will show one or more of the following signs: