Most of your carport will likely consist of sheet metal. The sheet metal will make up the carport roof and siding. Use sheet metal that naturally doesn't rust, or choose sheet metal that has a good rust-resistant coating. If a carport rusts, the rusty water will run off of it onto your car. Be careful when installing sheet metal, as its sharp edges can cut.
If you are building a carport in a new area off your driveway, you will need to lay down a slab of concrete to provide a clean, stable parking area for your car. You can purchase ready-made concrete, which will be delivered already mixed in a cement truck, or you can mix the concrete in a wheelbarrow or large bucket.
Metal rails and poles will form the supports for the sheet metal roof and siding. Place the poles vertically around the sheet metal roof to support it. Place the rails across the top of the poles to provide additional support. This support is especially important in areas with a lot of wind, which will threaten the stability of the metal carport. Use a post-hole digger to set the poles, and pour cement into the holes to secure the poles.