Choose curtains in such colors that they do not stand out from the overall picture of the interior. Pay attention to more calm and unobtrusive tones - they will create a quiet, comfortable atmosphere.
Here the curtains should be plain in the classic style. An excellent addition to such curtains will be lambrequins, brushes, eyelets. And if you do not like the details, hang ordinary curtains, but they should have a formal appearance.
Bet not so much on beautiful as on practical and functional curtains. They must be sewn from durable material that is easy to wear.
Personally, I like translucent or light curtains, blinds or Roman curtains are also good. Remember the colors: red helps to awaken appetite, while blue, on the contrary, suppresses it.