Weirdly, benign neglect (or, as I'm typing this list, I'm realising you have to treat them like gremlins...)
Don't put them in direct sun - indirect bright light is fine but they're woodland plants so no cooking them on a south facing windowsill
Also, try to keep them out of drafts and not right next to a heater - normal room temperature and fairly stable and they'll be happy
Don't let them stay wet - when you water them don't get water into the 'heart' of the plant, just hold the pot under a cold tap or over a sink and pour water over the roots and bark in the pot so it wets the potting mix thoroughly and runs out the bottom but doesn't gather in the middle of the plant and rot the leaves
Feed them by getting some orchid feed and making it up according to the instructions and just misting/spraying it over the plant once a week (or if you've only got one you can just get little spray bottle of the stuff. Poundland sell these a lot for some reason)
When they finish flowering, cut the flowering stem down, stop watering it and and put the plant somewhere colder (but sheltered/frost-free) for a couple of weeks to make the plant think it's had a winter, then bring it back to its normal spot and start watering/feeding it again
Don't repot them unless they've just finished flowering - if you do re-pot one, use another clear pot and a mixture of bark and sphagnum moss, dont pot them into compost/soil and don't pack them in too tightly, they usually grow a bit like alpines, in sparse soil on the sides of cliffs (or even in the bark of trees) so the roots don't need to be completely in contact with the potting medium and they benefit from being able to get some light
Hope there's something in there that you haven't already tried that helps!