For me it's all kept upstairs
That may work for your
Breechplug, but my "upstairs" has so many twists, turns and dead ends that I frequently get lost when I go there. However, I distinctly remember what I had for dinner this evening and I'm pretty sure my wife's name is Rosemary.
I have a file folder for each gun and keep just about all of the targets I shoot in a folder, with the targets numbered in sequence.
I almost always shoot five shots on each target and always record all of the load data on them - as you can see from the sample below. It's target #93 from my Great Plains flintlock and tells me I haven't shot that gun since last November. Damn, I need to shoot that gun next week-end.