Step 1: Set preferences
Open GarageBand’s Audio/MIDI Preferences panel and select the interface your guitar is connected to from the Audio Input menu. Close Preferences.
Step 2: Create new guitar track
To access GarageBand’s emulated guitar gear, you need to create an Electric Guitar track. Click ‘+’ in the lower left corner and select ‘Electric Guitar’.
Step 3: Instrument Setup
Click the Instrument Setup triangle to reveal a selection of menus to configure your track’s input and output settings. Click on each to adjust them.
Step 4: Enable monitoring
So that you can hear your guitar while playing, tick this checkbox to turn monitoring on for your created track. When ready, click the Create button.
Step 5: Select combo preset
GarageBand will add your new track to the project with a Clean Combo setting. To change the sound, click on the pop-up menu to display the preset list.
Step 6: Adjust tone
To fine-tune the sound, click on an amp or a pedal to reveal its controls in the lower panel. Click and drag on the knobs to adjust the settings.
Step 7: Set recording level
With the amp highlighted, click the Edit button. The amp will swing round to reveal the input source, monitoring and recording level controls.
Step 8: Pedal display
Clicking on a pedal in Edit mode brings up the 15 stompboxes. Just drag and drop one over an empty yellow pedal slot to add it to the effects chain.
Step 9: Record
When happy with the sound, click Done, then hit Record. You can tweak the sound after recording, as amp and stompbox effects are applied on playback.
Click on the image below to zoom in and read the annotations.