In SharePoint 2010 & 2013 designer, to copy an existing sharePoint list item with in the same List is not permitted, since it creates infinite loop of workflows when a workflow is triggered if a new item is being changed.
To Overcome this, I will be giving the list of the steps below:
  • Create a Check box with Copy Item as the Field Name in the Parent List.

  • Create a Dummy List for Parent List .

  • Add a List WorkFlow with the Parent List.

  • Add an action copy list item in the Parent List Workflow.

  • Add an action Copy list item in the Dummy List Workflow from Dummy List to Parent List.

  • Delete the current item in Dummy List Workflow.
In this way, we can avoid using any Custom components and achieve the funtionality using Out of the Box functionality.