New Messages

     Upon selecting the New button in the Control Panel, the above dialog is displayed.  It looks rather busy, but it contains all information that is necessary to define a Notify alarm.

Message Text

     The large box is for entering the text of the message that is to be displayed when the new alarm fires.  Note that messages are restricted to 255 characters.
     The Return key is significant within the text.  (Returns are ignored when the message text is not being edited.)  ⌘-X, ⌘-C, and ⌘-V have their normal clipboard interaction of Cut, Copy, and Paste.  In System 7, these commands are also accessible from the Finder’s Edit menu.

Sounds

     The two radio buttons in the upper right corner, along with the list below them, designate the sound that will accompany the message when it is displayed.  Selecting the Default Beep button uses the default system beep sound, or selecting any name from the list will use that sound.  Selecting the Silent button uses no sound at all.  Note that a selection is confirmed audibly.

Primary Date, Time, and Repeat

     The two boxes just below the message box are for specifying the date and time of the actual event that is the purpose of the message.  This is the date and time that will appear in the Control Panel’s list, as well as at the top of the alert when the notification is displayed.  The time may be entered in 12 or 24 hour format.  (Seconds are ignored if entered.)
     The pop-up menu just to the right of the Time field (here labeled daily) is for specifying how often the event occurs.  The menu offers the choices never, hourly, daily, weekdays, weekly, monthly, annually, and every…  If every… is selected, new text items are displayed in the days, hrs, and mins columns to the right to allow the the exact repeat interval to be specified in days, hours, and minutes.  If never is selected, it specifies that when the message is displayed this time, it should be automatically deleted instead of rescheduled.

Advance Alarms

     If you wish to be reminded of the event before it occurs, you can specify advance notices in the three rows that begin with numbered checkboxes.  A checkbox must be checked in order to use the row it is on.
     The columns labeled days, hrs, and mins (beneath the Date and Time fields) designate the first time that the particular row is used, relative to the primary date and time of the event.  If more than one row is turned on, the alarm scheduler will use only one at a time, changing from one to the other as it gets within the smaller time interval of the event.
     The advance specifications have Repeat pop-up menus similar to the primary event time.  The repetition begins as specified by the time interval, and then continues until the primary event time, or until a smaller advance iterval is encountered.  If never is selected, it specifies that the particular advance line is only used once per primary event.  (It doesn’t delete the message.)
     Note that even when advance notifications are displayed, the primary date and time appear at the top of the alert window.

Timeouts

     Messages are ordinarily displayed at the time for which they are specified, but when the Mac is powered up, there may be a backlog of messages overdue to be displayed.  The Timeout checkbox designates that a message that is too old to be of significance should be discarded instead of displayed.  The items to the right of the checkbox allow the meaning of “too old” to be specified, in days, hours, and minutes.
     For example, if a message is scheduled to appear at 8:00 every Monday, and has a Timeout of one day, then if you start your Mac anytime after 8:00 on Monday, you will see the message immediately.  But if you never turn it on Monday, and not until after 8:00 on Tuesday, then the alarm will be automatically rescheduled for the following Monday, and will not be seen this week.

Finishing up

     Clicking the Cancel button discards the message and returns to the Control Panel.
     To store the message, click the Save button.  For convenience, when the dialog comes up, Date and Time on will contain the current date and time, but the Save command will not exit the dialog unless they are changed to designate at least one minute into the future.
     If the Save defaults checkbox is checked when the message is saved, the primary Repeat interval, all advance specifications, the Timeout interval, and the selected sound will be saved as defaults for subsequent new messages.

Keyboard shortcuts

From anywhere in the dialog:
    ⌘-. or Escape selects the Cancel button.
    ⌘-S selects the Save button.
    ⌘-T toggles the Timeout checkbox.
    ⌘-X performs the Cut command.
    ⌘-C performs the Copy command.
    ⌘-V performs the Paste command.
    ⌘-1, ⌘-2, ⌘-3 toggle the checkbox on the appropriate advance alarm specification row.

When editing the primary date, time, or repeat interval, or when editing any advance alarm row, certain keystrokes will select items on that row’s Repeat menu:
    ⌘-N selects never.
    ⌘-H selects hourly.
    ⌘-L selects daily.
    ⌘-K selects weekdays.
    ⌘-W selects weekly.
    ⌘-M selects monthly.
    ⌘-A or ⌘-Y selects annually.
    ⌘-E selects every…

When editing any time interval, the “+” and “-” keys increment and decrement the current field, with carry to the more significant field if applicable.  When editing the primary date, “+” and “-” increment and decrement by days, “⌘-+” and “⌘--” by months.  When editing the primary time, “+” and “-” increment and decrement by minutes, “⌘-+” and “⌘--” by hours.

Example

     You have a meeting at 2:00 pm every Friday.  You want to be reminded once on Thursday afternoon in case you need to make advance preparations.  But starting at noon Friday, you need a nudge every half-hour.  So you just define two advance specifications as shown below.