Open your audio recording software. Under "File" select "New Project". Save the project as something you will remember such as "Voice Pitch Shift 01". Import your voice track into the program by selecting "Import" under the "File" heading. A browser window will open over the recording interface, allowing you to locate the file on your hard drive. Once found, press "OK" to continue.
Select the first effects input in your voice track. Select your "Pitch Shift" plug-in from the drop-down menu that appears in the effects input. The "Pitch Shift" plug-in's option window will appear.
Move the main pitch slider up or down the desired number of semitones. Two semitones equates to one step musically. Raising the pitch creates a younger juvenile voice sound (Alvin and the chipmunks if raised one octave). Lowering the pitch gives a very low sounding voice.
Play the voice track back to hear the sound difference. Adjust the main slider until the desired sound is achieved.