You can customize how FirstClass behaves in a number of ways. For example, you can change default fonts, apply background pictures to forms, connect to a particular window, and create an automatic reply for mail. To change a preference: 1       Choose Edit > Preferences.         Mac Choose FirstClass > Preferences. 2       Click the tab on the Preferences form that contains the preference you want to change. 3       Make the change. To change a preference without closing the Preferences form, click Apply. To reset all preferences to the FirstClass defaults, click Default. Caution When you click Default, all your preferences will be reset, not just the ones showing on the visible tab.