While there are many steps in replacing a flat tire, the most important thing to keep in mind is safety. While there are a lot of things that can go wrong, you can stay safe by following a few simple guidelines throughout the process.
Once you discover that you have a flat tire, you need to make an immediate assessment as to how far you can continue to drive on it. Ideally, you want to find an empty parking lot to pull into. If that is not possible, at least get over to the side of the road and out of the way of any traffic.
You will also want to use your hazard lights. If ever there was an occasion to use those lights, this would be the time. You need to let other drivers on the road know that you have a problem. This also alerts any police officer that might be in the area that you need assistance as well.