What are NFTs?

The first NFT was developed back in 2014, but it wasn't until 2018 that they began to gain serious popularity, with some selling for over $100,000. Since then, the market has seen dramatic fluctuations, allowing many individuals to achieve financial success.

A Non-Fungible Token (NFT) is essentially a unique piece of data stored on a blockchain. It can represent ownership of various digital assets like images, art, music, and videos. The uniqueness of NFTs lies in their ability to publicly verify the authenticity of the digital files. Through cryptographic hash functions, ownership and authenticity can be easily tracked and confirmed by anyone.

Setting Up Your Wallet

There are numerous wallets for storing NFTs, but this guide will focus on MetaMask, which is accessible as a Chrome extension and also as an app for iOS and Android. Here’s how to install the MetaMask Chrome extension, which is essential for minting NFTs. You can also use the MetaMask app to view your assets on mobile.

To begin, visit the MetaMask website and navigate to the download page for Chrome:

After installation, you can access your wallet via Chrome's extension menu, which will resemble the interface shown on the MetaMask website:

In your wallet, you can send and receive funds, as well as swap between various tokens. Clicking on your account name will reveal your MetaMask wallet address. Congratulations! You have successfully set up a crypto wallet with MetaMask.

Connecting to OpenSea

Now, navigate to OpenSea.io and create a new account. I recommend using the web browser version for this process, as the mobile app doesn’t support NFT minting (though you can still browse and trade). After signing up, click the wallet icon and select MetaMask:

This action will trigger your MetaMask extension to open, prompting you to sign a Signature Request. This step grants your wallet access to OpenSea, allowing you to list NFTs under your wallet address.

Creating a Collection

In OpenSea, you can set up a “Collection,” which is simply a grouping of NFTs. Under "My Collections," you can manage existing collections or create new ones:

To establish a collection, you’ll need a unique name and a logo. You can also add optional features like a banner photo, category, description, and royalty settings. If you wish to earn from NFT transactions, you can specify a royalty percentage (up to 10%) that you will receive upon each transfer of your NFT. Additionally, you’ll need to choose a blockchain for your collection. For this guide, we will mint an NFT on the Polygon Blockchain.

Once your collection is established, you are ready to mint your NFTs!

Minting Your NFT

With your wallet connected to OpenSea, you’ll find an option to "Create" in the upper right corner of your home page.

On this page, upload the file you wish to mint as an NFT, alongside its name. You can also add a description or link and categorize it within your collection.

Make sure to select the blockchain for deploying your NFT. The Ethereum Blockchain and the Polygon Blockchain are the two most commonly used options. Listing on Ethereum incurs gas fees, while Polygon does not. Should you choose Ethereum, ensure you have sufficient ETH in your wallet to cover these fees. On Polygon, you can also list NFTs with multiple copies available.

Click “Create,” and your file will be minted into an NFT!

Selling Your NFT

After minting, your NFT will appear in your OpenSea profile. To put it up for sale, click the “Sell” button:

You’ll be able to set your sale options, including how many copies you wish to sell and the price. A unique feature of NFTs is the ability to earn royalties from subsequent transactions.

After selecting “Complete Listing,” you will need to confirm the message using your MetaMask wallet. This will reopen your wallet via the Chrome extension, allowing you to sign the NFT with your address.

Once signed, your NFT will officially be for sale on the OpenSea Marketplace!