The longer story
The familiar tells, such as extra fingers, garbled text on signs, and unnatural blinking, are disappearing quickly as the tools improve. Treat them as a bonus rather than a method. The habit worth teaching is checking where something came from: whether a reputable outlet has reported the same thing, whether a reverse image search shows the picture in an older and completely different context, and whether the account sharing it has any history. Be most careful with content that arrives with a strong emotional charge, because material designed to make you angry or frightened is the most likely to be manufactured and the least likely to be checked before it is passed on.