I'm a tad on the absent-minded side, though not as bad as him. Some tricks have helped:
1. Establish regular simple habits, If you can get your routine down, you'll have all the normal habitual things.
2. Carry a big backpack (or suitcase, whatever). Just leave most things you'll need in it at all times. Then you don't have to remember them, they're just with you. Heavy I suppose, but you get used to it.
3. Pre-load. Instead of thinking "Must not forget X thing", put X thing in your backpack as soon as you're starting to worry about it. Again, then you don't have to remember it; as long as you have that bag, you've remembered everything.
With this I am no longer the guy who always forgets stuff and am instead the guy who always has everything you need in his backpack. Almost always, anyway.