How do you keep track of how many times you've used your brass?

[WelshShooter]

I keep brass in boxes which I batch based on number of times fired (i.e. all the three times fired brass are kept separate from the twice fired brass). I simply write on a piece of paper how many times they've been fired and what operations have been performed (e.g. sizing, cleaning, trimming). It's easy to pick up where I left on a brass prep session and also ensures that my loaded ammo is correct as that batch will have consistent case lengths when trimming is performed.