Watch out for where your users talk. Be timely to the signal. You can use free tools like trysygnal for that.

Close circle. Make something for your friends/family/colleagues. The best first customers are those that, right now, are in your phone's address book.

For me, paying for featured listings on launch directories (Product Hunt, There's An AI For That, PeerPush and few others) brought immediate, traffic with zero social effort that brought leads to start with.

Its not magic , you will have to work hard to get the users, but at least you will get some quality leads this way.