> Any other operation will be written on paper in a step by step well phrased manner.

Same exact experience, I cannot get my parents to think about what they are doing, they just follow the steps; if an icon changes or if the button is in a different place the whole workflow stops until I help them. Any suggestions here on how to improve the approach?

Avoid jargon/technical language, show practical steps and tell them what to avoid doing on the new system. (Last bit is important. I like to play around with new things to get to know them, but you need to avoid anything which crashes the system, erases etc.)