Fusion Scenario that uses custom form fields to update native fields in WF.

Hi All,

We have custom user forms attached to each user, that has accurate data pulling in from other platforms.  We want to use this data on the custom form to update native user fields in WF (i.e. telephone, city and state).  How would I go about creating a fusion scenario that uses preexisting data on the custom user form to update those native user fields? I also need the scenario to make updates to the native fields if any of those fields on the custom form get updated.

appreciate any suggestions/directions you could give me on this.