What some folks call political correctness I call respect. Being politically correct is simply acknowledging and adjusting what you say, and write, to adhere to the terms that are presently considered the most accurate.
Adhering to "political correctness" does have its challenges. It can be difficult to know what exactly is correct and to keep up with changes. or to choose between similar terms, and a host of other concerns. Of course, a sensitivity reader is an enormous help for flagging things are that not appropriate, but how do you prevent it?
Below are style guides from organizations representing marginalized groups, as well as, journalistic societies. These guides not only define terms but also directly state if they are slang, offensive, or simply outdated. Keep in mind these guides are intended for journalists which is good because they are current and thorough but don't take the context of fiction writing into account.