1) Ever get out in the field and find you forgot something important - I have been known to discover after a hike that no, my cable release isn't in the backpack. How about a check list yout type up - you could even laminate it but then it wouldn't be free - but you could probably afford it.
2) Anything you carry need batteries? Even large format photographers have light meters. Either carry spares or make sure they are fully charged before going out. Running out of juice in the middle of a shoot isn't cool!
3) Ever lost anything out shooting? Like lens caps, CF cards, or whatever - how about carrying a few cruical spares?
4) rely on a camera bracket or tripod or something that has to be tightened? Do you have the necessary Allan wrench or whatever to fix it - I keep the specific Allen wrench (just an L shaped piece of hexagonal metal rod) for tightening my Really Right Stuff L Bracket. The other day I found a tiny light weight socket wrench for my Gitzo tripod. I have once had the entire head of the tripod come off fortunately without losing the rig over the side - it's held with one nut - I now check it regularly.
5) there's nothing more chumpish than sleeping in and missing the good morning light - so check the time of sunrise the night before - don't assume - and remember the best light is often before sunrise so be on site an hour before sunrise - yeah - I know it hurts - but you have to suffer for your art - at least be there ready.
6) Take your first shot quickly, but do yourself a favour and before you move the camera, look through the view finder again - is there anything not quite right about the composition, if in doubt, move a little and shoot again - give yourself a choice of images to work with when you get home.
7) It's a nuisence to use the waist strap on the backpack but if your camera gear is heavy and you are walking any distance, do your back a favour and do up the strap and take a lot of the weight on your hips - much easier.
8) Have a metal tripod? - ever get cold hands carrying it? How about puting insulating round the legs so you don't get cold hands on those early morning Fall walks?
9) To avoid disappointment, have a backup plan. This might apply if the old factory you plan to photograph has been flattened and new apartments are under construction but actually I was thinking more of you go to your main shoot and are really busy, but it can be a good idea to plan a secondary shoot in the same area. Sometimes the main plan turns out crud and the 'oh what the heck, might as well while I'm here' photos turn out to be the winners. A matter of not puting all your eggs in one basket.
10) Be kind to yourself and don't set yourself unrealistic goals. If Ansel took 12 great shots a year, what makes you think you can do any better - or more to the point expect any better or demand of yourself better. He got 12 great shots in probably more than 50 trips a year (one a week), many of them lasting several days. You shoot for a few hours each weekend, some weekends, and really, when you add it up, you really only have 20 excursions in a good year, most lasting half a day or less. Right, so be kind to yourself and set yourself realistic goals. Anticpate that this trip might not produce a winner at all, but go out often enough so that some of them will and the pressure on any given excursion isn't that much. It would be silly to miss a lovely day out and some gorgeous scenery because you were so worried about getting 'the great shot' that you didn't notice the experience.
It is reasonable however to set yourself the goal of prodiving the printer (likely you) with the best possible exposures and as few as possible technical issues) - make the art part the only possible excuse for lack of winners and have a good time out there.