In Client Config, tab Order: Realtime, paste a YouTube embed URL (the https://www.youtube.com/embed/... form) into Realtime: Youtube - How to Video - Embeded URL Only and save. The ordering page then shows a "how to" button that opens the video. If the field is empty but Show Front Tutorials is enabled, Sprwt's generic tutorial video is used instead; if neither, no button is shown.