Recurring schedules allow you to create or send invoices on a recurring schedule. Schedules can be anywhere from once a week, to once every two years.
Find Recurring Schedules under the Invoices tab, then click Add Recurring Schedule.
Start by selecting a client from the dropdown. You can choose which of your client's contacts will be included on the schedule.
Next, set your schedule number. The Next Invoice Date is the date on which your schedule will begin.
Choose the due date that you want set when your invoice is drafted or sent. Frequency specifies how long the selected action will occur. Under Action, choose to have a new invoice draft created, or automatically sent to your client.
For help filling out invoice items, take a look at Getting Started With Invoicing.