Minting NFTs on Polygon for Low-Fee Transactions

🎯 Course Objectives

By the end of this module, learners will:

• Add the Polygon network to their MetaMask wallet

• Obtain MATIC tokens for gas fees

• Mint NFTs on OpenSea using the Polygon network

• List NFTs for sale on OpenSea with minimal feesY
  
  Primary Blockchain: Polygon (Layer 2 / sidechain for Ethereum)
  Tools/Platforms: MetaMask, OpenSea (set to Polygon network)

🧰 Step-by-Step Guide

1. Add Polygon Network to MetaMask

• Open MetaMask and click on the network dropdown at the top.
  
  

  

• Select "Add Network" and enter the following details:

  • Network Name: Polygon Mainnet

  • New RPC URL: https://polygon-rpc.com/

  • Chain ID: 137

  • Currency Symbol: MATIC

  • Block Explorer URL: https://polygonscan.com/

• Click "Save" to add the network.
  
  

  

Note: You can also add Polygon automatically via Polygonscan by clicking "Add Polygon Network" at the bottom of the page.

2. Obtain MATIC Tokens

• Purchase POL tokens from a cryptocurrency exchange (e.g., Coinbase, Binance) and transfer them to your MetaMask wallet address.

• Alternatively, use the Polygon Bridge to transfer assets from Ethereum to Polygon.
  
  

  

Note: POL is required to pay for transaction fees on the Polygon network.

3. Connect MetaMask to OpenSea

• Navigate to OpenSea and click on the "Connect wallet" icon in the top-right corner.
  
  

  

• Select MetaMask and authorize the connection.
  
  

  

• Ensure that MetaMask is set to the Polygon network.
  
  

  

4. Mint an NFT on Polygon via OpenSea

• Click on "Stuido" in the drop-down menu on the left side of OpenSea.
  
  

  

• Click on "Create" in the top right corner of OpenSea Stuido.
  
  

  

• Select the type of mint you would like to do
  
  

  

• Upload your artwork file (supported formats include JPG, PNG, GIF, MP4, etc., up to 100 MB).

• Add a title and description for your NFT.

• Under "Blockchain," select "Polygon" to mint on the Polygon network.

• Click "Create" and sign the message in MetaMask to complete the minting process.
  
  

  

Note: Minting on Polygon via OpenSea is gas-free due to lazy minting, where the NFT is minted at the time of purchase.

5. List Your NFT for Sale

• Navigate to your newly minted NFT and click "Sell."

• Choose your preferred sale method:

  • Fixed Price: Set a specific price for immediate purchase.

  • Timed Auction: Set a starting price and allow buyers to place bids over a set duration.

• Set the duration for the listing.

• Click "Complete listing" and sign the message in MetaMask to finalize the listing.
  
  

  

Note: OpenSea charges a 2.5% fee on the sale price.