Open your preferred audio production program, such as Cubase, Logic or Pro Tools. Double-click the desktop icon or select the program from the "Start" menu. If you are using a Mac, you can open the program by clicking the desktop icon or selecting it from the "Applications" menu.
Plug the female end of an XLR cable into a microphone. Plug the other end of the cable into the "XLR In" jack on the front of your audio interface. The audio interface converts audio into data before sending it to your computer.
Plug your headphones into one of the outputs on the rear of your audio interface. Click "Settings" and select "Outputs." This opens a menu that allows you to configure your output settings. Click on the output you are using for your headphones to access their specific settings. Select "Master." This configures that output jack to receive the master mix from the production interface rather than just the audio that is going into the track at that time.
Click "File" and select "New Audio Track." Assign Auto-Tune to that track. The method of assigning an effect to an audio track differs slightly according to which program you are using, but effects are typically located under "Effects" or "Plug-Ins." Effects sub-menus are typically divided according to the type of effect. Auto-Tune is a brand name. If you haven't specifically installed the Auto-Tune plug-in onto your system, select "Auto Pitch Correction" or "Auto Correct" from the menu. These are generic versions of the effect that function and sound like Auto-Tune.
Click on the channel strip of the new audio track to highlight it. Click "Settings" and then "Effects." Select "Send to Master Bus." This configures the channel so it sends real-time data, as well as the audio, to the master bus.
Enable recording on the new audio track by clicking the "R" icon. This sets the channel ready to record audio that it receives from the audio interface.
Turn down the "Master Volume" dial on the audio interface. Put on the headphones and sing into the microphone. Gradually adjust the "Master Volume" dial to your preferred level. As you sing, you'll hear the Auto-Tune effect on the mix.