Well I don't do this for runs. Every run uses the same amount of shells each time so i've already remembered it but when i was first going through the game that's how i slowly learned and remembered the shells if that's what u mean

What I found to help with remembering the longer loaded guns is to use snapchat on my phone to write down what is what easier, i.e: i take a pic of my desk so its blank, then I right B - L (blank / live) and i write down how many were in the case and every turn i update it underneath.