Duo with Secure Remote Desktop via RD Gateway
With Duo, you will be connected to your remote computer the same way as before. (Refer to Secure Remote Desktop instructions if needed). For example:
Enter your HS credential as you normally would and click OK.
The difference is that during the "Initiating remote connection..." process, you will be prompted for second factor authentication by Duo. If you have Duo Mobile app installed on your mobile phone, you can have a push notification sent to you. If you don't, you can opt to receive an automated phone call.
For instance, on your computer screen, you may see:
While on your mobile phone:

Duo Push Notification

Phone call (answer, press 1 to login)
Simply respond to the push notification or phone call (from 714-456-3333) with the appropriate action to complete your connection.
If you are not getting push notification or phone call, please logon to the Self-Service Portal to make sure a working number is listed as your primary device.