On Writing Diversity
I will admit that I am somewhat hesitant to write about this, mostly because talking about race in fiction can quickly devolve into some sort of Fail. However, I do think writing race and diversity is a subject worth thinking about and discussing, and I ask that you please keep the comments cordial and on-topic. (Related to that, no tone policing or derailment, please.) I will keep mostly to discussions of race because that is what I feel the most comfortable addressing.
First, I would like to address a few pervasive and damaging myths when it comes to writing. The most important: Am I allowed to write outside my own race? The answer is: Of course you are. You are allowed to write whatever you want. But instead of asking, Am I allowed? I think the better question is: Is it appropriate? When is it appropriate? When race is treated thoughtfully and as an organic part of a character (i.e., not exoticized or otherized). When is it inappropriate? When it is tokenism. "Appropriateness" and "appropriation" are two related, but distinct ideas a writer needs to keep in mind when it comes to writing racially diverse characters and settings. The first is easier to deal with. With research, by asking thoughtful questions, and having readers vet your work, the question of whether or not it is appropriate to write outside your own race is mitigated. Can you describe your character without referencing their race/ethnicity, their looks, or what they wear? Or is their race simply shorthand for stock and stereotypical traits? Think about these questions carefully and be honest about the answers. The second is...complicated. It's complicated because individual sensitivity to cultural appropriation can vary quite widely. If you are writing about a setting and/or culture not your own, proceed with caution. Appropriation most often happens when the writer is "outside" the culture and looking in. This "outside-in" viewpoint is problematic because it very often leads to exoticization and othering. Let me explain about exoticization and othering, and let me explain with personal experience. Growing up, there weren't a lot of characters like me in the books I read, and if there were, they were inevitably made to seem Other. Here is the default, the books seemed to say, white, heterosexual, able-bodied, and middle class. The default seemed to be the only type of person worthy of being the hero of his/her own story, as the not-default acted as props to further the default hero's narrative. You know what they say, "Three times a bridesmaid, never a bride." Always the Sidekick, never the Hero. Or, on the other hand, if the not-default had his/her own narrative to carry, then inevitably the story was about the not-default's Otherness. (The so-called "issue books": coming out stories, racism stories, Old World vs. New World stories, etc.) All of this subconsciously leads the not-default reader into thinking s/he isn't Normal. We all want to feel normal. That's really what writing diversely is about: normalizing the vast array of human experience. If you can conceive of a race or a culture foreign to your own as Normal, then that mentality goes a long way in avoiding appropriation in fiction. Tropes to think about and avoid when writing outside your race and/or culture (WARNING: You WILL lose hours of your life on this website, clicking and clicking and clicking....):
Cultural Tourism
The White Man's Burden (related: White Knight-ing)
Going Native (related: The Dances With Wolves Problem)
...and many more!
If your work happens to contain one or more of these tropes, it doesn't mean you are a horrible person, but it does mean that perhaps you ought to take some time and think about why your work contains these tropes. It may mean that you have neglected to imagine your characters complexly. The truth, as John Green says, resists simplicity, and so does being human.