Download the Metamask wallet browser extension or mobile app.
If you're new, click Create a Wallet. If you already have a compatible wallet, you can also select Import Wallet.
Your wallet information is extremely important and very sensitive. If you lose your seed phrase, no one can recover it for you which means that your account, along with your tokens and items, will be lost forever. Please take the time to create a strong password and to securely store your recovery information.
Step 2 - Add Polygon to Metamask
In Metamask, click on the current network which is Ethereum Mainnet by default. At the bottom of the list of networks, click Add Network.
Now copy and paste the following details:
Network Name: Polygon Mainnet
After filling in all the details, click Save. You will now find the newly added Polygon Mainnet in the network list.