If you would like your Users to manage their own access PIN codes without you generating the PIN codes you can go to Settings > look at PIN Settings > enable "Generate PINs automatically for all users". This will allow your User base to manage their own access PIN codes instead of you having to generate PINs for them to use.
User's Perspective: User would go to their Profile Screen> click on the "+" icon to create an Access PIN code or to edit they would click on the "Pencil" icon. Refer them to the Swiftlane App Manual