So for a story I think it really depends on how deep you’re planning on delving into these characters personalities.

If they’re side characters you can just do a surface read of trans culture to add flavor to their description, but you don’t want to overfocus on it (if you’re new to lgbt stuff I would suggest not making a side-character’s queerness overly plot-relevant. It comes off as tacky and as cheap pinkwashed inclusivity).

For example: Erin sits next to Emily and goes to remove her bag. Somehow the conspicuously pink blue and white strap manages to catch her hair for no discernable reason. Emily rolls her eyes and starts to unravel the knots and tangles. The annoyed furrow in her brow deeply contrasts with the doting gentleness in her practiced hand movements.

It’s a bit silly and rough, but above we establish that Erin and Emily have been in a relationship for a long time. References to their queerness are kept to a minimum and are just woven in to how they interact with eachother (the important part). And the facts we can glean from this can be used to provide context for how the rest of the scene will go, why the two of them react to things a certain way, and what decisions they might make. And we can do that without needing to make overt references to their queer status any more than we already have.

Now if you’re trying to do queer main characters, I’d suggest being in the community for a while. There’s no advice or story I can give you that will fully encapulate who we are or how we’re to be portrayed because every context is different. The same depiction can be pandering or cruel or exceptionally clever depending on the subtle things you can glean just by being around us and internalizing the experience. You can make the world’s best attack helicopter joke, better than anything the chuds could do if you can understand and empathize with us innately (I wouldn’t recommend it, but there’s a transwoman out there who’s done it). Like, if you only glean details from second-hand stories, it will be obvious, because there likely won’t be any subtlety, even if you’re trying really hard.

A good queer MC needs to have their identity planned out from the beginning, it needs to shape how they perceive characters, situations, their own place in the world, and even facial expressions or small little happenstance details others might not notice. It will affect what they obsess over, how they focus, where they direct their energy, what they value. But you have to be able to say these things without being like “his transness transed his worldview” or “xe just couldn’t see [thing] the same way after becoming nonbinary.” Like, this is one of those situations where you actually have to follow the ‘show, don’t tell’ rule very closely.