First, bring up the Reminder calendar by clicking on Reminders in the Moneydance Sidebar (or by going to the Tools->Reminders menu item). To create a new reminder click on the appropriate date in the calendar, or on the + (plus) button at the bottom right of the page, and select "Create Transaction Reminder".
The Reminder Description field is for your information, and is used in the reminder list to the right of the reminder calendar.
The First Date is the first date the reminder will occur on, the (optional) Last Date is the last date the reminder will occur.
Reminders can occur one time, or can be Repeated. A repeating reminder offers a number of different date “tabs” (Daily, Weekly, Monthly, and Annually). A reminder will occur on all dates you specify in ANY and ALL tabs.
Reminders can be applied manually or auto-committed. Selecting “Auto-Commit” will enter the transaction in the appropriate account register a set number of days before the transaction is scheduled.
Select the appropriate Account by clicking the up/down arrows. Enter a Description, Category (or multiple categories using a split transaction), and Payment/Deposit amount. You may also choose to enter a Check #, Memo, or Tag(s).
To delete a reminder click once on the reminder in the right panel of the reminder calendar, then click the - (minus) sign at the bottom right of the page. To edit a reminder double-click on the name of the reminder in the right panel.