The Periods step creates the time intervals to be used in the scheduling calendar.
Click on the wizard 
icon to open the Generate Periods Wizard.
- Use the blue plus icon to add new Periods.
- Use the dropdowns to set repeating time intervals and overall duration.
- Inspect the results in the Preview table on the right.
- Toggle the options and naming conventions as required.
- Press OK to finish.
If you are modifying an existing schedule, remember to update the calendar values for new or modified periods.