It is often the case that you have to perform multiple similar simulations. To avoid doing the same work multiple times you can prepare only one simulation as a template, duplicate the template case and then just perform the necessary modifications.
In order to duplicate existing case:
In the launcher window click the button to display all the available cases.
In the list of cases click the next to the case you want to duplicate to display options for this case.
In the popup menu select the option.
In the dialog window specify the name of the new case and click OK. You can optionally also copy the result files.