Presented below are ten photography tips I've picked up over the years. Some of it's obvious, perhaps, some of it less so. They're - except for the first - in no particular order of importance. While I shoot only film, most of these apply equally well to people shooting better digital cameras; those with digicrapcams are pretty much out of luck, as usual. This is not meant to be a "Photography 101" lesson, or a "how to", or a ridiculous exposition about "rules" of composition, rather a mere few tricks and tips for those already halfway competent with cameras.
Tripods. More photographs are probably ruined by camera shake than all other causes combined. Get a decent tripod, and you'll have one fewer thing to worry about. New inexpensive tripods aren't worth the pot metal they're stamped out of, but the amateur tripods of just a decade or so ago were vastly better than the crap peddled by Wal-Mart today. If you don't want to spend $150 on a decent new tripod, spend $20 for an used Velbon, Slik, Star-D, or similar all-metal tripod from the '60s thru '80s at your junk store, thrify shop, or auction website of choice. They're stable and virtually indestructible, and weigh about the same as decent modern tripods, though they may be slightly bulkier. Most even had interchangeable heads. The same caveats about modern tripods apply to vintage ones - leg braces just add weight, and geared centre columns add weight yet impair stability.
Lens Shades. A lens shade really should fitted to every lens you use, and it should be there for every picture you take. There are a lot of shades and hoods out there, either OEM (and expensive) or third-party (and cheap). As long as they're the right size for your lens, cheap hoods made in India, China, or Pakistan really are not one bit inferior to the pricey versions made by camera and lens manufacturers. Metal or plastic doesn't really matter that much, but avoid rubber shades, even the expensive ones - they deteriorate quickly when exposed to sunlight, and will rot and split. If you happen to have a camera that takes 40.5mm filters, or any other less-common size, you may find that the available hoods are few and frighteningly expensive. Not to worry, just get a $10 metal adapter to a larger thread size, and use a hood that fits the adapter.
Tape. Specifically, cloth surgical tape. I prefer 3M Durapore(tm), but use whatever you like. Surgical tape is strong, can be easily written on, and doesn't leave any residue behind when peeled off. This makes it great for taping gels over lights, attaching oversized filters or hoods to lenses, securing flash sync cables, and labelling things like sheet-film holders. Seriously, I carry a roll of this stuff in my camera bag, and it's one of the most useful things to have around in the field. If you want to write on it, naturally you'll need something to do so with. Mechanical pencil, ballpoint, or whatever else suits your fancy, get a couple and leave them in your camera bag.
Portrait Film. Lower-contrast professional print film, at ISO 160 or 400, also sometimes referred to as wedding film. It basically comes down to a choice between Kodak and Fuji these days. Pick whichever you prefer, or whichever's cheaper - they're all pretty much the same, and very, very good. Even if you never shoot portraits or weddings, keep a couple of rolls of portrait film in your refrigerator. Inevitably, because you're a photographer, some friend, relative, acquaintance, or coworker is going to beg, cajole, or bribe you into shooting photos of people - either for a wedding, an engagement, holiday gifts, or some other reason. Portrait films work far better for this kind of thing than consumer print films, or ultra-saturated slide films, and not everyone likes or wants black-and-white photos. If you're new to photography, reading this, and think I'm nuts, just wait. You'll thank me one day.
Warming Filters. 81A, 81B, or, if you're adventurous, 81C. Outdoors, these color-correction filters slightly warm your photos by very slightly limiting the amount of blue light that passes thru them. Even if you're shooting print film, where color correction can be applied when printed, Try using an 81-series filter. With older lenses, and even many modern zoom lenses, the reduced blue transmission reduces to a small but meaningful amount veiling flare within the lens itself, and can produce a useful increase in apparent contrast. Try it - it works.
Flashlights. A penlight, if you're elderly, or a pocket torch, if you're English. It's no fun trying to read aperature and shutter-speed markings by the light of a crescent moon, much less find a dropped black lenscap in the grass. Also useful for composing at night. If you're trying to take a photo with an SLR of a fountain or other object at night in the dark, it can be extremely hard to tell where the edge of the frame is. Stop guessing if your shot is centered - shine a light obliquely on the front of the lens, and your prism and viewfinder will light up like a flare-prone wonderland, easily letting you see what's where.
Bounce Flash. On-camera flash sucks, but bounce flash, even on-camera, sucks a lot less. Don't be tricked into buying a $300 gee-whiz dedicated flash with a 100-page instruction manual and more buttons than a vending machine. The Vivitar 283 and it's posh brother the 285 have been serving hundreds of thousands of photographers well for close to thirty years, run on AA (UM-3) batteries, and are both available new for under $100. There's also a huge cottage industry of companies offering a nearly endless variety of accessories for these powerful (GN 120 at ISO 100) flashes.
Flash Bracket. On-camera bounce flash is a ten-fold improvement on plain old on-camera flash, but getting that flash off the camera, even if it's only a few inches, can make a hundred-fold improvement in your pictures taken with flash. Unless you're working on a tripod, or have three arms, you'll need a flash bracket. A simple L-shaped, handle-style bracket is more than enough for most people. You may also find, if you have arthritis, carpal-tunnel problems, or a very small camera, that a handle bracket is a lot easier and more comfortable to hold.
Cable Releases. Even if you're not hauling around a tripod (shame!), a cable release - or two, one of modest 6-12 inch length and the other perhaps half a metre or two feet long - should be in your camera bag at all times. Sure, you may say, why on earth would you want to use a cable release without a tripod? I'm continually surprised by the number of photos I take where the camera is resting atop a fence post, or sitting on a window-ledge, or otherwise not being handheld, yet not mounted atop a tripod. Even if you're shooting at 1/500 second, a cable release will prevent you from bumping the camera, and can be rather easier to use than tripping the shutter the conventional way, especially if you've picked a cramped or otherwise unusual vantage point. If you have a camera that doesn't accept cable releases... get a new camera.
Rope. Or cord or webbing. A purpose-made strap for a tripod costs about $30; five feet of one-inch tubular nylon webbing (used for rock climbing) costs less than $2, and works just as well. In addition to this painfully obvious use, your rope-like material of choice can also be used to tie or lash your tripod to all sorts of things. I've tied tripods to chain-link fences, trees, and even stepirons in a sewer manhole shaft, in order to get a shot from the vantage point I wanted. Sure, you might be able to improvise with your camera strap - but if it's a halfway decent strap, it'll have all sorts of padding and buckles and quick-releases and other things that get in the way of a good, strong knot... and what are you doing with a camera strap that isn't halfway decent, anyway? A nice complement to a rope or cord is a decent carabiner; it will set you back $10, and comes in astonishingly useful for hanging camera bags, or whatever else, from things - ladders, fences, tree branches, the mullion of a broken window...