1/ Install Metamask Browser Extension https://metamask.io/

2/ Create an account

3/ Unhide Test networks and select "Rinkeby test network"

4/ Get some ETH from faucet https://faucet.rinkeby.io/ or https://rinkebyfaucet.com/ or https://faucets.chain.link/rinkeby

5/ Mint your NFT and Play the game !