The first step is to go on and locate all the studs in the wall. You will need to use a stud finder to do so and your primary goal should be to mark out all the studs and their locations with a pencil, in order for you to avoid them altogether.
The next step is for you to mark out the area of the door. You can do this by using a pencil to make a rough sketch of just where your door will be going in. However, in the end, it would be smarter for you to make a more precise outline of the door, since any fumbles could result in a very ugly hole in your wall.
Now you need to take a sharp cutting tool and move it along the outline that you made on the wall. The tool will help cut through the initial paper surface of the wall, which is what you want to do at this point.
Don’t go on and try to apply too much pressure or it could ruin your plans.
Once you have cut out the paper area, grab a hammer and break out the wall inside the marked area. Use different sized hammers to ensure you get a decent break out and so that no debris are left behind.
The next step is to get the door and put it in place. After you do this, you can attach its hinges using a screw driver, or a machine which would aid you to do the same thing.
Once you are done placing the door in, you can smooth things out using a smoothing tool and you can even apply some finish to the door and the wall to make it look smoother and like it had been built that way to begin with.