Try Salon Lulu in Wooster Square. It’s one guy and a receptionist. I went to him a few times last year and he was great about masking. I have an older, covid cautious friend who still goes there so I’m guessing he’s still taking precautions, but not sure. Definitely worth a shot.

I also know a stylist in North Haven who will cut hair outside in warm weather, but she’s booked solid for the next few months, and the salon itself is more lax in their precautions.