How do I import a network into MetaMask?

For those just diving into the world of cryptocurrency and its many wallets, the process of importing a network into MetaMask might seem daunting. Could you break it down for us, step by step? Specifically, I'm curious about how to safely and securely import a new network configuration, whether it's a popular network like Ethereum or a less common one. I'd like to know what precautions to take, any necessary software updates, and any specific steps that need to be followed. Is there a chance that I could accidentally import the wrong network? Could you offer any tips on how to avoid common mistakes during this process?