Click on the "Track" menu on the menu bar. Select "Add Track."
Click on the track once it appears on the left side of the screen. Select the "Track" menu again and choose "Audio Options."
Click on "Device" to choose your microphone. Click "OK" when finished.
Click the "Rec" button on the track to arm the track for recording.
Click the red circular record button on the main instrument panel to begin recording. Click the square stop button when finished.
Rewind to the beginning of the track and press the "Play" button to hear what you just recorded. While listening, adjust the mic volume to the level you want by moving the "Volume" slider in the track window.