Here are the steps on how to enable this option for the donation section of your event.
 

  1. Go to Communities > Special Events > Friends asking Friends > Kintera Thon
  2. Hover over the event you wish to edit and select Website Info
  3. Click Donor Giving Levels and Participant Incentives
  4. Click the check box for Set up recurring payments
  5. Edit the Maximum # number of payments you want available (you can have 2-60)
  6. You can enable pre-defined frequencies by checking either the Monthly, Quarterly, or Yearly, check boxes
  7. Click Save
  8. Go to the Webinfo Checklist
  9. Click Publish This Event Now
PLEASE NOTE: 
Recurring donations are not supported on mobile donation forms. The above steps will enable them for the non-mobile donation form for your Thon event, but they will not show up as an option on the mobile version.