Our jobs around computers often center on solving problems. When the momentary euphoria of solving a problem ends, and we move onto the next problem.
The idea behind a developer journal is that making relevant notes as you go about your tasks can help the future you.
Even if you work with a tool only briefly, being able to reference your journal the next time you use the tool can limit that loss of muscle memory and improve your recall.
I have found a developer journal useful tool to use. I use typically text documents or this blog as my journals.