Great question! I worked on a banking app that included live mockup previews for ID uploads. I started with a template base from https://fakeidtemplates.org/driver-license-maker/ to overlay user images and data fields. Using JavaScript, we allowed users to drag and position their photo within the guide frame, then displayed the final composite before they hit submit. This reduced mismatched uploads by over 60%. Key things to remember: provide clear alignment markers, enforce aspect ratios, and offer real-time feedback if the lighting is too dark or the text is blurry. A simple “retake” button right below the preview can boost completion rates significantly.