There is no nip, nor gold standard. It's a bit of a mess, and not looking like it's going to get better any time soon. The canonical form is to use your pubkey, but that will have different states on different relays. There is a hack which lets you combine pubkey with a relay using nprofile, it amounts to having a query string, and that is nprofile. You can also share via nip-05 user@host which provides a two way binding with your pubkey, tho that will change over time (unless you have something like single use-seals, or git, or both). Sites such as https://nostr.at/ (which is a fork of njump dot me without the spyware) do a reasonable job in finding your profile. https://nostr.at/npub1au23c73cpaq2whtazjf6cdrmvam6nkd4lg928nwmgl78374kn29sq9t53j ... this is a big problem in nostr because profile is what ties everything together and critical to UX. It's not going to get fixed anytime soon, and may well get worse. Sites like nostr at do the best job for now, and you can use nprofile but be aware it's a hack. tl;dr there's no best pracitice in nostr, just different hacks