This quote from Beth Comstock is a nice heuristic for spotting emerging trends.
Another way of looking at this is through writing.
If you notice something and find yourself writing it down three times in a short space of time, you may have just spotted a trend.
Go back to those notebooks and look for the patterns.
Who knows what you may find.
PS. I’m putting together a recorded version of a class I did on Trend Spotting (including the above Beth Comstock quote plus a bunch of other tactics and exercises) – that’ll be going live next week.