There's no real text book as the craft is new, always changing, and each job is different.
I'd recommend some practices:
Color coding your work station to manage cards/media - I have a red box on the left of my system for "hot / exposed" cards and a green box for cards ready for format - that I've downloaded, verified, and visually QC'd. Once they're done, they go to the green box, until being relabeled, formatted, and reshot on. Full circle.
I would also recommend creating a spreadsheet to track your download activities. I log the Roll number, the name I gave the card (IE If i have four cards, I name them after the ninja turtles, so if there's a card issue I know which one it is) the amount of data on that card, the amount of clips on that card, and checkboxes for making 2 backups, and one checkbox that I've QC'd the material.
Other than that, a good DIT always helps the DP / camera dept once his own responsibilities are taken care of - so have good set ettique at know what AC's need - batteries, a coffee, extra tape, something from the truck, I even track down cigs for the crew when I'm not busy - anything to make them remember you as very helpful - they're the ones hiring you most of the time!