Forms Library

If you want to copy a form from the Form Library, start by clicking the Form Library button in the Dashboard Menu on the left. This will bring up a list of folders.  Click on the folder of your choice.

Clicking the folder brings up the forms in that folder.
Notice that at the right are Preview and Use buttons.

Clicking the Preview button brings up the form in preview mode.
If this appears to be what you need, click the Use button.
Select the folder to copy it to. In this case there is only the default folder, so that is selected.

Back on your account
Forms area, you will see the Copy of the form you copied.

Back on your account Forms area,
you will see the Copy of the form you copied.

Click on the form name, rename it, add or delete pages
and reorder pages as necessary to fit your custom requirements.