How do I stay safe?

I’m considering meeting up with a man who won’t tell me how or where we know each other from, only his first name, which doesn’t ring a bell, that he’s autistic and that he knows me. He told me not to worry and that I’ll know him when I meet him. That sounds ominous to me, though. On the other hand, I’m really curious. How do I stay safe, if I decide to meet him?

How do I stay safe?
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