One of the first things you ever want to do when getting started in the Web3 space is to set up a “wallet”. A crypto wallet is just what it sounds like — a virtual wallet that stores your tokens for different cryptocurrencies. Wallets have also become your way to log in and authorize yourself with decentralized applications (DApps). So with that said, it makes sense why having a wallet of your own is one of the first steps you need to take.

Why MetaMask?

There are a lot of different options when it comes to choosing which wallet you want to set up. Personally, I really like MetaMask because I find it very user-friendly in its interface and extension, and it’s widely supported. I often come across a lot of smaller DApps that only support login with MetaMask.

It’s definitely one of the most popular wallets currently being used, and you won’t hesitate to find any amount of tutorials on it.

Setting Up Your Wallet

Firstly I have an entire video tutorial walking you through this process, so if you’re a fan of video tutorials, be sure to check that out! Otherwise, let’s get started:

Step One: Install MetaMask

You can install MetaMask as a browser extension at metamask.io. It’s supported on Chrome, Firefox, Brave & Edge, so as long as you’re not stuck in the days of Internet Explorer, you should be good! 😂

If it’s your first time setting it up, I highly recommend watching the video of the Secret Passphrase. It’s incredibly important to understand what it is and to keep a copy of it safe and secure.

Once you’ve finished setting it up the extension should look like this:

Step 2: Add the Polygon Network

You can add the Polygon network easily by going to https://polygonscan.com/. Scroll down to the footer and click “Add Polygon Network”.

This will prompt you in the wallet to add the network. It will flag a warning at the bottom asking you to verify that the chain ID yourself. The Chain ID for Polygon is 137, and it’s always a good habit to get in the habit of confirming that ID is correct for extra security when you aren’t manually adding a network yourself. The network is called “Matic Mainnet”, since Matic is the currency of the network.

If you prefer to manually add the Polygon network, you can do so by clicking on the “Ethereum Mainnet” in your wallet and then selecting “Add A Network” at the bottom of the dropdown menu.

You can fill out the new network as follows:

Now your network should be set up and look as follows:

And that’s it! As far as the Polygon network, the setup portion is complete. You can add money to your wallet by clicking on “Buy”. It will assist you through Transak, which is their integrated way to purchase crypto.

Step 3: Using The Wallet To Buy on OpenSea

So now what? Well, that depends on you. For the sake of this tutorial, we are going to discuss purchasing NFTs on OpenSea. OpenSea is one of the largest marketplaces for NFTs and it supports the Polygon chain. However, they don’t process payments with Matic but actually use ETH on the Polygon chain.

This is where a lot of people get confused but don’t worry, I’m going to walk you through it.

In your wallet, you’re going to hit the “Swap” button. You will need to have the amount of Matic you want to convert already in your wallet, plus a little bit extra for the gas conversion fee.

Once you’ve done that, enter the amount of Matic you want to swap to ETH, and search for ETH (Ether) in the “Swap to” section, as shown below:

You will then see something similar to this:

This highlights the conversion: how much ETH you’re getting for the Matic you’re converting, as well as the estimated gas fee. Once you’ve confirmed the amount is correct, you can go ahead and hit swap.

I want to point out that this is actually WETH (Wrapped ETH). You can read more about OpenSea using WETH here.

Once you’ve converted the amount it will show it as either ETH or WETH, depending. They have the same contract address and are the same token for the sake of working with OpenSea.

How it displays after I swap the token (as ETH):

How it displays when I “import” the token (as WETH):

Now, you can go to OpenSea and purchase the NFTs of your dreams! Connect OpenSea with your wallet and you’ll have your OpenSea account. The first time you make a purchase on the Polygon network you’ll need to “Unlock” the currency, which is a one-time fee. Then you’re free to buy as you wish!

If you found this article helpful and enjoy my educational content, I want to express my thanks, as well as share that I offer a lot of exclusive educational content for holders of Boos!, an NFT project that I lead. It would be fantastic if you would check it out, and it’s the perfect NFT for newbies because any holder gets access to the locked section of our discord where you’ll have access to chat with our devs and creators, as well as access to all the educational content that is exclusive to our holders (and we have lots more coming)!