Switching to a proxy user role

When this procedure is complete, the user for which the proxy has been created can switch to proxy mode. To switch to proxy mode, from the Start menu, select Switch To Proxy. If the user is a proxy for more than one actor, a list of the actors for which they can be a proxy is displayed. The proxy user should select the actor for which to do work. When proxy mode is in effect, a message is displayed. The message is:
nnnn - Proxy Mode For xxxx.
Where nnnn is the current actor and xxxx is the actor for which the current actor is doing work. When the actor is done with any proxy work, they can select Switch Back From Proxy from the Start menu.
Note: 

If you are using Manager Self Service, this is under User Preferences.