To buy or sell NFTs on Sotheby's Secondary Marketplace, you'll first need to create a Sotheby's Metaverse account and complete the necessary legal and compliance checks. Afterward, connect your digital wallet to your account. To purchase NFTs, browse the available offerings and pay with the approved cryptocurrencies, depending on the network of the NFT. To sell NFTs, you must have your artwork approved by Sotheby's specialist teams, as only approved artists and collections are eligible for listing and selling on the platform.