I have a cipher that I'm trying to decode. It's quite lengthy, so I started trying do do a simple substitution. I checked the frequency and noticed that every letter in the alphabet was used - and multiple times.
I don't think the letters Z, Q and X would be used as much as the least frequent letter though. I noticed that there are a lot of duplicated "words". So, my next idea was to find a keyword to use. The only problem is that the letters that aren't frequently used (X, Z, Q) are some of the most frequent letters. I can't imagine what keyword would contain those letters.
I've been searching for different ways to decode this but have come up short so far. I'm not looking for an answer, I stubbornly want to do this on my own. I'm looking for some ideas, or guidance from someone who is far more experienced. Is there some sort of checklist to go down to figure out how I need to proceed?