Step1.Add EventHandlingScope Activity Under OnWorkflowActivated

Step2.Add SequenceActivity In EventHandlingScope Activity

Step3.Add EnableWorkflowModification Activity

　　a.Bind [ContextData] to a new field

　　b.Set [Colorrelation Token] as "Modification" and [OwnerActivityName] as " your workflow name"

　　c.Generate guid for [ModificatiomId]

　　d.Bind a method to [MethodInvoking]

Step 4.Switch to View Event Handles mode of EventHandlingScope

Step 5.Add Event Driven Activity in View Event Handles mode of EventHandlingScope

Step 6.Add OnWorkflowModified Activity in Event Driven Acticvity

　　a.Bind [ContextData] to the field we create at step3

 　 b.Keep [Colorrelation Token]  and [OwnerActivityName]  same as step3

　　c.Keep [ModificatiomId] same as step3

　　d.Bind a method to [MethodInvoking]

　　e.Bind [User] to a new field.

Step7.Modify Element.xml of the workflow

　　　　a.Replace the guid string in Modification node

Step8.Verify