An important precaution is to make sure no electrical cords and wires can be chewed. These should be wrapped up and tucked away. You should also make sure that any cleaning chemicals in rooms such as kitchens and bathrooms are out of reach. It's best to make sure your dog can't get into any cabinets because seemingly harmless items can prove to be dangerous. Trashcans should also be out of reach or closed securely.
Houseplants can also pose problems because they can be knocked over and possibly eaten.
This should be avoided because certain plants are poisonous to dogs. Also, it is usually a good idea to get some baby gates to block off certain rooms and staircases. You will also want to make sure your yard is safe. This includes making sure your fence is secure so that your dog can't get out and other animals can't get in. Also, fence off any pools and flower or vegetable gardens.