What do you do if someone asks you out ?

Im honestly just kinda curious as to how other people handle it, like what do you say, what do they say etc

Because since starting university I’ve been asked out/ppl have shown interest in me a couple times now and I always mentally freak tf out on how to reply.

I told one person that I just wasn’t looking for a relationship, and I told another that I’m aromantic (I had to explain it to her) but I’m wondering if anyone else has any stories or advice on this topic 💚