The STAR method is great.

And it's worth emphasizing that you're also interviewing them. Absolutely because you want to make sure you actually want to work there, but from an anxiety perspective, it gets them talking and that takes pressure off of you. To me, the hardest part of interviewing is the feeling that I have to put on a performance and the less time I spend feeling like I have to be "on," the better.

And to that former point, if there are things that they're doing or along that are making you anxious, that's something to take into account. I had one interview where I was asked a lot of weird, irrelevant questions to "test" my personality. It felt like they came straight from some bullshit, pseudoscientific article about how to vet job candidates. That's not the kind of workplace I want to be in.