Create a new Logic music project. Open your "Macintosh HD" folder, in the upper-right corner of your desktop, and select the "Applications" folder from the left column of the pop-up window. Logic appears among your applications. If you do not have Logic installed, you can purchase it from Apple. When Logic opens, click "File" on the menu bar and select "New" from the drop-down menu.
Enter specific information for your song. When your new project loads, you will see a pop-up window with the words "New Tracks." Enter the number of tracks that you want to see, based on the size of your project. Your tracks are your recording layers, with a different track for each section of your recording. For example, if you intend to have two guitars, a drum and a vocal section, you might want to insert four tracks, one for each section. To do that, enter a number "4" in the "Number" box. You can always add more tracks later by clicking "Track" on the Logic navigation bar and selecting "New" from the drop-down menu.
Enter the types of tracks you want to use. In the same pop-up window, Logic will ask if you want to create "Audio" tracks or "Software Instrument" tracks. Select "Audio" if you want to record using analogue instruments like guitars, drums and microphones, and select "Software Instrument" if you want to record digitally using Logic's software synthesizers (this will require you to connect a MIDI keyboard to your Mac). Then click the "Create" button.
Hook up your music equipment. If you want to use Logic's built-in software synthesizers to generate sound, plug a MIDI keyboard into your computer, using a MIDI cable and MIDI-to-USB converter cable. Plug the MIDI cable into the "MIDI Out" jack on the back of your keyboard, and into the "MIDI In" jack on the face of your converter cable. Plug the converter cable's USB connector into your Mac's USB port, indicated by the three-pointed USB symbol, resembling a trident. If using traditional instruments to record, plug an audio interface into your USB port for the cleanest sound, and plug your instruments and microphones into the interface. An interface is an external sound card that connects to your computer and includes jacks for all of your musical equipment, available from most music supply retailers.
Record music onto your individual tracks. The amount of tracks you previously selected should now appear as a stack of long, horizontal bars, spanning across your main "Arrange" window. To begin recording on any of these blank tracks, click the title of the track in the left column and press the red "Record" button at the bottom of the screen. Begin recording your guitar, keyboard or other sequence in time with the beat as the metronome ticks. To record music using Logic's digital software synthesizers, double-click the track title to open the mixer, and click the "Input" button on your selected track. As you hold down the mouse button, a list of your software instruments appears. Select an instrument from the list and begin playing notes on your MIDI keyboard.
Record additional tracks to layer your music. In order to create a complete, multi-layered composition, your recordings must line up on top of one another in their respective tracks. Your time line appears horizontally at the top of your main window, and dictates the timing for each recording. For instance, if you record a guitar riff on "Track 1" starting at "0" on the time line, and record a drum beat on "Track 2," also starting at "0" on the time line, your guitar and drum will play at the same time. Keep stacking recordings until you have the necessary number of layers for your song.
Add effects. Click the title of any track to open the mixer, and choose effects by clicking the "Inserts" boxes on each track bar, and selecting your desired effects from the drop-down menu. You can add distortion, reverb, pitch correction, delay and other effects to get the perfect sound for each track.
Save your finished song as an audio file. Click "File" on the Logic menu bar at the top of your screen and select "Bounce" from the drop-down menu. Enter a title for your song in the "pop-up" menu, select an audio format such as MP3 or AIFF, and click the "Bounce" button.