This video illustrates how to change the pitch, speed and tempo of an audio file. The first thing you need to do search online for the website for "Audacity" or "Audacity Editor". Once you find it and get there you next need to download it and save it to a location in your computer. Next, open it and run the program. When you are done installing it and you hit the"finish" button you can select your audio and make the changes you need to it.