How do I add Starknet mainnet to MetaMask?

Could you kindly elaborate on the steps involved in adding Starknet mainnet to MetaMask? I'm a bit unfamiliar with the process and would greatly appreciate a step-by-step guide. Could you please start from scratch, explaining how to access MetaMask and navigate to the necessary settings? Also, would you mind clarifying any specific requirements or prerequisites that might be needed before attempting this addition? Thank you in advance for your assistance.