Open the Logic song project that you want to edit. Click "Window," "Mixer" on your menu bar to access your digital channel strips.
Click to highlight the channel strip corresponding to your vocals. For example, if you recorded your vocals onto the "AUDIO 1" track (on your main project window), then click the "AUDIO 1" channel strip on your mixer. The channel strips are directly linked to your recording tracks.
Click any of the gray "Inserts" boxes on your selected channel strip. Choose a box that does not already have an effect selected. In other words, choose a box that appears blank, with no words written inside. On the pop-up menu, hover your mouse over the "Enhance" option and select "Pitch." A new window will appear, featuring your pitch-editing options.
Click "Scale," "Major." In the "Root" box, select the specific key of your song. If you do not know it, select "Chromatic" in the "Scale" box, but note that the Auto-Tuning effect will not sound as precise.
Drag the "Response" slider until the number in the box reads "0ms." This will apply an ultra-sensitive pitch enhancement effect to your vocals, resulting in the kind of robotic vocal arrangement heard in many dance, pop and R&B songs.
Close your "Pitch Correction" window and return to your main project window.