However some standard objects do not have this button. For this purpose of cloning we will need to create custom button that will perform the functionality of cloning.
As an example lets create a custom button "Clone" on account that will clone the record.
Simply override your custom button "Clone" with the following java script and you will have your custom Clone button that functions exactly like standard clone button
retUrl specifies the location where you want to be on press of back button.