We have talked about writing men, writing women and writing about other cultures. I think most agree that having some experience in your subject helps, but if you have no experience it doesn't limit you, provided you do the work. One of my pet peeves is workplace dialogue that is not believable. But then I always placate myself, by accepting that most writers don't have a lot of varied workplace experience to draw from. I have noticed a lot of first time novelists write about their own workplace. Oddly, although I've had an interesting career, I chose not to write about my own workplace for my first crack at a novel. Fortunately, I have found a number of great books on my protagonist's career, and some written in first person which is very helpful. However, I am curious to know how others approach this. What type of research do you do to write professions and workplaces? What other techniques do you use to make it believable?
I'm in the fortunate position of a history/fantasy author where nobody really has experience with the workplaces I portray. After all, we don't really have a House of Nobility, military has changed quite a lot and thank heavens police doesn't work like the gendarme or the Kronstadtwacht. For each of the above I seek to approximate their atmospheres, functioning and hierarchies by finding "anchors" in real life from history and my own experience. Approximating can be the key for anyone; though it still works best with a wide spectrum of personal experience. For the House of Nobility, I draw from present UK house of Lords & their peerage laws since the 1700s. For military, I immersed myself with Napoleonic journals and literature to understand the setting both from the perspective of the simple infantryman and the greatest generals. And for the city guard, there's lot to learn about historical guard organizations, my main inspiration is the Scotland Yard. TL/DR same's true; keep the order of validity for research; Personal experience > Personal contact to someone with experience > Experienced person's writing > Random articles And also true that you should search around & research until you feel confident enough to write, then /not/ write but dive deeper and push yourself over the Dunning-Kruger pinnacle.