Replacing an exterior door is a big job, but it's one that you can do yourself if you're willing to put in the time and effort. Here are the basic steps: 1. Remove the old door. This will involve taking out the screws that hold it in place, as well as the hinges. 2. Prep the opening for the new door. This involves making sure that the framing is square and that there is enough space for the new door to fit. 3. Install the new door. This will involve attaching it to the framing, as well as installing the hardware. 4. Paint or stain the new door to match your home's exterior.

The first step is to measure the width and height of your door opening. You'll also need to take into account the thickness of the door and the space required for hinges and a handle. There are a variety of materials that exterior doors can be made from, such as wood, steel, or fiberglass. The most important factor in deciding which material to choose is the climate in which you live. For example, wood doors are a good choice for homes in mild climates, but they may not be adequate in areas with severe weather conditions. Once you've selected a material, you'll need to choose a style and color that will complement your home's architecture.