For clients using Apple products, here's a helpful animated GIF that you can email to them.
It also is great to put on your website to explain how the save-to-home screen feature works with iOS in an easy-to-understand way.
Unfortunately, due to the inconsistency with Android/Windows devices and operating systems and how this feature works on those devices, we don't have an animated GIF for Android/Windows phones.
Download High Res version here: https://www.dropbox.com/s/ehcgrzb31jgqh4v/iPhone%20Save%20to%20Home%20Screen%20Animation.gif?dl=1
Low-res preview: