Puzzles and Motivation

I bought a book about puzzle making in the hopes I could put puzzles into my stories, not word problems necessarily, but puzzles that were hidden in the text, and maybe help solve a mystery novel I'm working on. The reader doesn't have to see the puzzles to solve it, but if they can spot any puzzles it could help solve the story.  I've found a couple I'm going to try and use actually, one or two I found I'm going to build into the plot, and one subtle puzzle I'm trying to build as part of the story, but not part of the plot. Sorry if that's vague, but you can't give away everything.  Anyway, I've been trying to find puzzles I can build, which is really the premise of this book I'm using as research, the problem is its confusing. The language is well...confusing. Bet you thought I was going to say puzzling right?  Its confusing to understand, I was hoping I could learn how to build my own puzzles not try to cypher simple English.  How do people crack codes, or solve the unsolvable?  The puzzle aspect isn't all that important, they're going to be visible, but they're also going to be invisible too.  I get bored easily so I'm trying to do things that keep things interesting, I figure if I get bored others will too, and what better way to get somebody to read your story over and over again if they know there's something there but haven't found it yet?