Besides adblock + auto updates, tell them how some of the scams work. Show them some example screenshots/videos etc. from different areas. Enough to make them think twice about what they are allowing to run on their computer. Scammers are usually lazy, many times their email addresses, website address, or web design might give it away - so doing a few side by side comparisons may help.
There's also a lot of youtube videos that could be easier to send and less boring to go through. Ex:
- https://www.youtube.com/embed/bjYhmX_OUQQ?rel=0
- https://www.youtube.com/embed/DXfrfbNk7jo?rel=0
- https://www.youtube.com/embed/poFAzDCGLrI?rel=0
- https://www.youtube.com/embed/5zlnI3Bzslo?rel=0