Well, an airlock isn't super necessary, but if you can make a makeshift one that would be best. Once it's totally done fermenting, you can pretty much just cover it up while it ages. As for yeast, dry yeast is available online and is very cheap to ship so that really would be best, but if that's not an option, bread yeast makes a decent mead- not sure how it would work in cider but you could give it a try. Another option may be to find a bottle conditioned beer and grow up some yeast from the bottom of that bottle and save it each time you make a batch.
I can't be arsed to keep up this list of what's in the fermenters, but hey, check out the cool brewery I own!
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