FileMaker Auto-saves everything. When you disable auto-save in layout setup, it still auto-saves, but now it asks permission before doing so.
I tend to avoid this option due to the interface complications it causes. Can you describe your layout in more detail? That may enable us to suggest an alternative.
One method is to use global fields to record user input and then a "save" script creates a new record and copies the data from the global fields to the matching fields in the new record.