When you create a form for your customer, that form gets its own unique address.
You can add it to the Home screen (or save it as a bookmark in a browser)
iPhone (Safari)
Open the form in Safari. Use the unique link you have been sent.
Tap the share icon (the box with an arrow pointing up).
Choose "Add to Home Screen".
Type the name you want for the shortcut (Booking with xxx) and confirm by tapping "Add".
Android (Chrome)
Open the form in Chrome. Use the unique link you have been sent
Tap the menu icon (three dots in the top right).
Choose "Add to Home screen" or "Install app".
Confirm the name and tap "Add".