From having seen a lot of these threads, it feels like I would...
<snip>
2. Avoid having things you want treated like people (so, PC races) have biological/species parts that are just negative traits ("usually evil") or a set of traits that obviously fit with stereotypes that were used by real world racists/bigots against real life racial/ethnic minorities - especially when parts of the physical descriptions line up with the real world caricatures too (you can google those both in history, games, and books by famous authors). Unfortunately for creators, sometimes it's hard to see these at first, but once they're pointed out they're obvious to lots of people. And unfortunately, like with everything, there is a borderland where folks won't agree on if it's obvious or that bad. (Tangentially, I imagine an example of a race that tends to be very deadly when angered and is based on a certain dog breed as a justification... and then watch the defenders of that dog breed get angry about it.)
3. Someone will want to make lots of things people - so if you want something always evil maybe make it tied to an evil outer plane or undead or something like that (demon-cursed Gnolls, if they hadn't had a history of not being demon-cursed; vampires; far realm infested abberations). That won't solve everything, but see (6) below.
<snip>
6. Realize that you won't make everyone happy