Open the project you are working on from the Apps screen.
While in the UI Design module, open the Properties panel on the right.
From the + ADD ACTION menu, add the Process Automation > Set Agent action according to the trigger event you want (Initial Actions, OnClick, OnBlur, etc.).
Configure Action Parameters
User Name (String - Required): The username or email address of the user who will assign the proxy.
Agent User Name (String - Required): The username or email address of the user who will be assigned as a proxy for the task.