Thank you. I have that set up in primal but I can’t seem to find how to do it on nos social. Is that feature maybe not available yet ?
This will depend on what client you are using.
But really you just try to zap someone, and the client you are using (primal, Iris, Amethyst, etc see image) should tell you that you need to connect your wallet.
If you need more help nostr:npub1gzuushllat7pet0ccv9yuhygvc8ldeyhrgxuwg744dn5khnpk3gs3ea5ds is the right person to help you!
Have a nice day!

Discussion
I don't know exactly since im an android user and I cannot use nos, but seems that they released a new version recently and I can see zap related things in their changelog. Maybe update?
Yeah I downloaded it today so hopefully it’s up to date. It appears as tough there is no zapping feature (not yet) but I did receive a notification when some zapped me so I’m guessing they must have used a different app