Nostr: How do I create a Nostr identity?

Short answer

Choose a trustworthy Nostr client or signer and use its account-creation flow to generate a keypair. Save the private key or recovery material securely before posting. The public key becomes the durable identity others follow; your display name and profile details can change. You do not need a NIP-05 address or paid relay to create the basic keypair.

Sources

NIP-01: Basic protocol, NIP-19: Human-readable encodings, NIP-05: Internet identifiers.