My family and I binge watched The Marvelous Mrs. Maisel last night in an effort to stay awake until midnight for New Year's, and I was struck by how much everything matches in her house. In one scene, her completely color-cordinated pink kitchen even matches her dress. How did this work? My kitchen is a mixture of cabinetry included with the apartment, inherited things, things I found cheap in stores, and things I purposely invested in. I can't imagine buying everything at once from one retailer just so it would match - especially since in this scene she is living in an apartment and would presumably have to move every so often as rent changed. What if her next apartment had green cabinets?? What if her grandmother died and left her blue cutlery?? Was this matching a real thing or is it a TV invention? If it was a real thing, how did it actually work on a realistic level?
Yes, color-coordination in the 1950s was a real thing. Making sure your drapes matched the carpets (and throw pillows and wallpaper and stand mixer and telephone) is something that people took into account when furnishing their homes.
Even though we are talking about a period only 60+ years ago, it is difficult to say with any certainty the extent to which people color-coordinated their homes. The most widely available visual records of that time are movies, television, and advertisements. These obviously showcase the "ideals" of how the design industry believed the burgeoning consumer market should spend their newfound postwar prosperity. For real-world examples of the varying degrees to which people actually color-coordinated their homes, your best bet is to look for clues in old photo albums.
For how people would go about color-coordinating their homes, obviously starting with a blank slate, say one of those split-level ranches in the new housing development out in the suburbs, would be the easiest method. At that point one could seek out an interior designer or anyone who knows color theory, and have them do the work.
Or, armed with such guides as the 1956 short film entitled Color Harmony for Your Home produced by the advertising firm Rippey, Henderson and Bucknum, Inc. which takes color theory and turns it into an infomercial for Colorizer Associates's brand of paints, one could do it themselves by going to the local department store, Sears & Roebuck for example, walk through the various floor displays, and pick out a bedroom set, a living room set, a dining set, and all the necessary accent pieces, decor, and appliances, and have it all delivered to their house.
Using color theory also works if you had already amassed a collection of home furnishings and were moving to a new place or just wanted to refresh things a bit. If you jump to the 17:00 mark, the film discusses how to color-coordinate old things with new things.