I never had the discipline. Instead, I really enjoy reading the signs from weather, tide, a coarse level personal knowledge of run timing by location and variability in response to conditions, , etc. and making a decision to go fishing or not. Then on the water it happens at a finer scale, what gear to use, which hole to fish, when to move. Reading the water. Watching the birds. In short, I enjoy observing the circumstances and responding to them more than relying on a history of what happened before. The accumulated knowledge is in my head.

Now days, a lot of people look at the internet and see what happened yesterday to make thier decisions. Probably better than a journal if you dont yet have the instincts developed on how everything combines to influence fishing success. But I know a lot of people who make good use of a journal, so if you think it will help go for it.