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As a basic strategy, it is worth searching for use of a technique when you have already tried everything easier to look for and not found anything useful. In the long run, other factors come in, such as the odds of the search being successful, where you get your puzzles (different sources emphasize different techniques) and what you personally enjoy doing. But those are considerations you only need to worry about once you have more experience.
By the by, this ends up being a fairly personal decision. I search for fish very early, but some people never look for fish at all. Similarly, I mostly ignore Wings, while others look for them reasonably early.