Journaling is a powerful tool. Not just for stuttering. Journaling allows you to keep an objective record. Our memories are pretty selective and biased. You might find all kinds of associations you wouldn't have previously considered... Sleep, diet, exercise, environment, alcohol, school, work, family, etc. e.g. I have better fluency on days where I get at least seven hours sleep. Except those in which I drank the night before (I'm just making this up, but you get the idea.)