But one thing that is a rule which the average Joe should know is that no admins will ever send you a DM first. None.
Newbies might not know about this vital rule and when they knew about it, it's very possibly they were scammed and lost money already.
It's helpful for newbies if they can gain knowledge about most common scam types. That is their good start and preparation for avoiding scams but the remaining things belong to their self control ability and practice.
The Cryptocurrency Scam book.