For simple editing tasks, you can use the Sound Recorder that comes with Windows. For more complex tasks, you might want to purchase a more sophisticated sound-editing software application. You will also need a sound card and computer speakers.
Step1
Open your sound-editing software. If you are using Windows Sound Recorder, open it from the Start menu. (Choose Start, then Programs, then Accessories, Entertainment and finally Sound Recorder.) Step2
Click Open from the File menu, and then locate the file you want to edit. The file opens. Sound files contain a series of vertical lines of various lengths. They resemble the "lie detector" images that you often see on television shows. Step3
Move the slider to the place that you want to begin or end the cut to delete part of a sound file using Sound Recorder. From the Edit menu, click Delete Before Slider or Delete After Slider. Step4
Go to the Effects menu to change the speed of the sound file, and select Increase Speed or Decrease Speed. Step5
Select Increase Volume or Decrease Volume from the Effects menu to change the volume. Step6
Click Reverse in the Effects menu to reverse a sound file. Step7
Click Add Echo in the Effects menu to add an echo. Step8
Click Revert in the File menu to undo changes. Step9
Click Save to save your changes. Once changes are saved, you cannot revert. 
