Download 'Wallet of Satoshi' from any app store. An email address is your way to login if you get logged out.

In the wallet press receive. Find and copy the namenumber@walletofsatoshi address (your lightning wallet address)

Go to your Nostr client profile settings and paste it into the 'LN Address' box, then save.

That's it, let me know and I'll test if it works. Then you can zap and be zapped.