How to create, buy, and sell NFTs on OpenSea marketplace

OpenSea is one of the earliest (and now largest) marketplace for NFTs in the form of collectibles, gaming items, domain names, digital art, and other assets on the Ethereum blockchain. Here’s how it works.

How to create, buy, and sell NFTs on OpenSea marketplace

Wednesday April 13, 2022,

4 min Read

2021 was undoubtedly the year of NFTs (Non-Fungible Tokens), with the term emerging as the Collins Dictionary word of the year. 

The sale of an NFT by digital artist Beeple (Mike Winkelmann) for $69 million in 2021 opened the floodgates for scores of other NFT sales by various artists, musicians, actors, and regular users.

With NFTs gaining more use cases day-by-day, innovation is being spurred in startups working on blockchain-based digital asset ownership solutions.

In the last year, OpenSea  - an online NFT marketplace founded by Devin Finzer and Alex Atallah in 2017 - has emerged as arguably the dominant NFT marketplace.

OpenSea is one of the earliest (and now largest) marketplace for NFTs in the form of collectibles, gaming items, domain names, digital art, and other assets on the Ethereum blockchain.

On the platform, users can create, buy, sell, and trade NFTs with each other in a decentralised manner. This means no central authority - not even OpenSea - will act as a custodian for the digital assets.

OpenSea allows NFTs to be sold at fixed prices or through auctions. Since the entire infrastructure is built on Ethereum, the NFTs on OpenSea are based on the Ethereum ERC-721 standard, and can be traded on Polygon - a layer 2 scaling solution for Ethereum.

Following heightened interest in NFTs, OpenSea’s trading volume reached $5 billion in January 2022, and its valuation touched $13.3 billion in the same month.

NFT Development

Here’s more information on OpenSea’s features, and how users can create, buy, and sell NFTs on its platform.

Getting started with OpenSea

OpenSea’s main feature is its decentralised marketplace for NFTs, whose operations run across Ethereum, Polygon, and Klatyn. Any NFTs based on these blockchains can be traded on OpenSea.

Polygon, which has emerged as the most popular Ethereum scaling solution for fast and affordable transactions, allows OpenSea users to access and make trades on the NFT marketplace in a gasless (no fees) manner.

As a new user, an individual has to first register their account on OpenSea and connect their MetaMask crypto wallet extension to it (other wallets such as Trust Wallet work too).

Once the wallet is connected to the OpenSea account, the user can personalise their account page by adding a username, profile picture, bio, etc.

The user can then navigate to the ‘Create’ option, fill in the details of the NFT they want to mint, and proceed to mint it on the blockchain. The ‘Create New Collection’ option in the user account section can be used to mint NFTs under a certain user collection.

On OpenSea, NFT creators also have the option of adding unlockable benefits or exclusive perks accessible only to the owner of a particular NFT.

Users who mint their NFTs on Polygon need not pay a transaction fee, but minting on Ethereum incurs a network fee.

Some NFT platforms offer a free minting service as well, but take a percentage of the final sale price. OpenSea also takes 2.5 percent of each transaction that happens on its platform.

While it doesn’t cost anything to create an account on OpenSea and browse collections on its marketplace, there are two initial fees that need to be paid.

The first is a one-time gas fee for initialising a user account for placing sell orders. The second is a fee for allowing OpenSea to access user items or collections (which may not originally be minted on OpenSea) when a sale occurs.

Buying and selling NFTs

After creating NFTs on OpenSea, users can list them for sale by navigating to the digital asset and clocking ‘Sell’. They can then can choose to set a fixed price or a timed auction. With a timed auction, a potential buyer with the highest bid when the time runs out will acquire the item.

Once sold, the user has to sign a transaction on their wallet to confirm the sale.

The primary currencies for receiving and making payments on OpenSea are ETH/WETH (wrapped Ethereum), SOL, USDC, and DAI.

To buy NFTs on OpenSea, a user has to explore the marketplace and find an NFT they wish to purchase, and review its price history and confirm its details in order to avoid any red flags or scams.

For NFTs with a fixed price, the ‘Buy Now’ option can be used to further review the purchase before navigating to the checkout page and clicking ‘Checkout’.

After reviewing the applicable transaction fee in the crypto wallet, the user can then confirm the purchase and view the NFT in the ‘In-Wallet’ section.

For NFTs in a timed auction, the ‘Make Offer’ option can be used to place a bid (which must be at least five percent higher than the current bid) in the accepted currency of the user’s choice. An expiration date can also be set for the offer.

Edited by Megha Reddy