Create a recurring appointment that automatically schedules every month.

From the customer's location page, click the Create a new... button and select Work Order

On the Billing tab add the service description, adjust the price, if necessary, etc.

On the Schedule tab, select the tech.

Select the frequency Monthly.

Under Select Day(s), click the week of the month you want to schedule (clear the current selection if it is different than the default). In this example first is the default but we're selecting last.

Clear the current selection if it is different than the default. In this example the service we want to schedule is on the last week of the month.

Select the day of that week. As with the week of the month, clear the default selection, if necessary.

First service date... match this date to the Select Day(s) week of the month and day of the week. (For example, if it's the last Tuesday, select July 30.)

For all Frequencies other than One Time, the Select Day(s) must match First Service Date. Otherwise, you'll have two appointments the first month. In this example, the last Tuesday in July 2019 is July 30.

Enter the Duration and Start Time. 

Click the Save button and you have a series created in that customer's Work Orders tab. This example shows a monthly series starting on the last Tuesday of every month at 2:30 PM. 

The system generates a year's worth of appointments. As the newest appointments are completed the system appends the end of the list with additional appointments so you never have to remember to create more services. 

See these articles for creating other Work Order frequencies:
​How to create an Annual Work Order Series
​How to create a Seasonal Work Order Series
​How to create a Semi-Annual Work Order Series
​How to create a Tri-Annual Work Order Series
​How to create a Quarterly Work Order Series
​How to create a Bi-Monthly Work Order Series
​How to create a Weekly Work Order Series
​How to create a Daily Work Order Series