Really all I need a warning for is suicide and (real) spiders. Like the first thing really only becomes a problem if I'm not prepared for it but yeah.
And honestly I don't? Really retweet a lot of the typical things that people ask to be tagged (like nsfw images, as an example) and if I do I give a warning before I tweet and after.
But if you have something specific you want me to be mindful of, just let me know.
I currently tag insects, nsfw, and homestuck.