The very first thing I can recommend is to very rarely close your folding cameras. The only time I close my cameras is for air travel...they always remain open otherwise.
replace most of the camera, or just buy a new camera if it is a cheaper model. So it's easier to just keep the cameras open and dust them off every so often. Protecting the lens isn't really an issue when the camera isn't in a bag or something. This doesn't apply at all if you use a hard case camera, like the Big Swinger 3000 or Colorpack III, of course. though I suggest keeping your plastic cameras out of the sun for storage, as they tend to become brittle and shatter with age. If you do have leaks in your bellows, they will almost always be along the folding edges, specifically the points. All of that opening and closing causes these points to become weak and thin, and little pinpoint holes form.
I have tried a few different methods to repair light leaks, including small pieces of tape, black paint, black sealant, glue, etc. The best fix aside from replacing the entire bellows is to run electrical tape along each edge of the bellows. Anything you paint on there is eventually going to crack and fall off, and using small squares of tape on each individual leak is difficult and they tend to unpeel and fall off. I did this for the first time in a motel in Kiryu, Japan when I discovered that my bellows were super leaky. It was after 8pm and there was one single department store open, and all they had was red tape. It worked, and it is good visual representation of what you need to do.
Also, those plastic front masks:
Other than that, there isn't much to caring for your actual camera.
If you have shutter problems, first check that the cable is connecting. When you push the red button, it just pushes a wire into the back of the shutter mechanism, pushing up on a plastic piece that fires the shutter. Sometimes the little silver plate is loose and isn't holding the cable in place. Easy check before you start worrying about the actual shutter.
So, be nice to your camera. That's the best daily care advice I can give. Sure, you can always buy another for most cameras, but you will probably learn to love the one you have and not want to give it up.
As for your Polaroid film, try to store the unused packs in a dry, cool place. I put mine in ziplock bags and keep them in the fridge. The ziplocks are used because there is a lot of moisture in the fridge and your packs will rust if given the chance. But open dry air will probably make the developed dry out, as well. So you want to try to maintain them "as is".
Okay, so some tips for shooting on the field. One of the main questions I get about peel-apart film is how to carry them, particularly after they have been peeled. It's a moot point with integral as they are self-contained, though the Impossible films are very quirky in their own ways, and plenty of shooting tips can be found on the Impossible Project website. Peel-apart, or pack film, is a bit messier. First thing, get yourself a couple plastic bento boxes.
Skorj, who used them to keep his Type 665 in water in the field. I find that they are good for all pack film Polaroids. Polaroids fit in them perfectly, and they are mostly airtight (though I see water bubbling from that little plastic circle on top if I am storing 665).
Tokyu Hands in Shibuya, and then found the exact same boxes a mile from my home in Phoenix at an Asian grocery store. Easy. Stickers are not included, but make them a little bit cooler.
For the most part, you do NOT need to peel your prints at the recommended times of 30 to 90 seconds. Most peel-apart films are self terminating (meaning they stop developing after a couple minutes), and can be peeled hours after shooting. They will dry out if you leave them in open air, making backwards peeling virtually impossible, though the prints will be fine. But if you keep them in a bento box, they will stay moist for six to eight hours after you shoot. Depending on what I am doing or where I am, I will often carry unpeeled prints around for half a day and then peel them when I get home or at least to my car. I actually like to leave them for at least an hour because the developer along the paper edges is much lighter and dry when you backwards peel. It will be super dark if you peel right away and smear if you touch it.
So I say most peel-apart films will last a long time unpeeled in a bento box. There are a couple films that have to be peeled sooner. Type 689 keeps developing and gets darker and darker if you don't peel it (and actually develops more until it is dry). Type 667, 672 and 664 need to be peeled within 10 minutes or so, or the negative dries to the print and is tough to peel off, and you will get mottling on your print. Fortunately, these films dry very quickly, so carrying one around for a couple minutes usually isn't a problem. Then I still use a bento box to protect them until I get home. Other than that, I don't think I've ever had a problem with any other film. Type 669, ID-UV, 690, Viva, etc., all can be peeled hours later. Fuji films, FP-100B, 100B and 3000B, last a long time as well, and you will often find that the print has separated from the negative side on its own with Fuji films.
The downside to peeling much later is if you don't trust your exposure, you might have 10 poor shots instead of one. I think of it as kind of the same as shooting with film...try to do it right the first time because you don't know what you are going to get until later. Sometimes I will peel my first print to see how I've done in a peculiar light. A baseline print is sometime needed, particularly with expired Polaroid film, as one pack can have a very different ISO than another.
Also, you want to save a bit of the extras with some films. Type 87, 667 and Fuji FP-3000B all have goop side negatives that can be scanned.
The other part you might want to save is the negative for Fuji FP-100B and FP-100C (and the 45 versions as well), which can be cleared with bleach for scanning.
Those are my basic shooting tips. I don't use a light meter, but with expired films you may find it to be useless anyway. Sometimes the ISO is super slow with older films. Experimentation and experience help exposure. I have for a long time used an ND filter on my 190 and 195. These were made by Polaroid and can be found on eBay. I paid 11 bucks for one of them, so don't pay $150 like some are asking. There are also Polaroid made UV and orange filters, as well as a hood, for the 180/190/195. There are also some filters out there for the auto folders, though I don't have much experience with them. The cheaper plastic cameras shoot as is.
More recently, someone has made a filter adaptor for the 180/190/195, allowing you to use 46mm filters on your manual cameras, which opens up a new world of filtering for your peel-aparts. I've done a bit of messing around with warming filters, but more on that in another post.
That's all I can really think of right now. If you have any specific questions that haven't been answered here or in other posts, ask below and I will try to answer or provide links. Here are some links to previous Polaroid posts that I have done that may help:
Polaroid peel-apart examples
Polaroid peel-apart guide
Polaroid peel-apart guide part 2
Polaroid integral guide
Polaroid manual camera guide
Hope this was useful! Until next time...