How to Duplicate a Doctype to Reduce Time Spent on Customization

Can any one kindly show me how to duplicate DocType. For Instance, I want to duplicate Quotation DocYype and use as another DocType. How do I do that with the underlying codes working even if I need to duplicate the child table too?

Thank you.

@Otunba go to doctype list , open your doctype click options then duplicate

Please look at the error message I got while trying to duplicate the Doctype “Quotation” and rename it “Prop”.

How do I solve the problem?