Aloha! As a simple trader, I treat cycle as a very simple concept. It's whatever that repeats after a certain duration. For instance, the 4 seasons comprise a cycle. We all know that they come and go after 3 months with spring coming before summer and summer before fall and fall before winter (in that very particular order). That has practically never changed since time immemorial. It's the same thing in the market. You try to find a pattern that repeats time and time again. Sure, not easy by any stretch. Here's a hint though: Don't think in terms of a shape (eg, sine or sawtooth) but in numbers (eg. time and price).