A word of note:

You can obviously change anything you want.

But make sure that you are following these 10 timeless copywriting principles while editing/writing your emails for best results:

• Don't use formal language. Instead, talk as if you are the customer's friend.
• Sell the result, the educate the customer on the process.
• Write copy for 1 reader. Speak to “you”, not “everyone”.
• Sell the result, not the process
• Organize information into lists
• Don't oversell the problem. Just say what it is
• Sell the benefits, not the features
• Share 1 shocking stat.
• Be clear, not clever
• Be a painkiller, not a vitamin.