When you sit down to write your sales letter, you first identify your best customer. You identify his or her age, marital status, location, income etc. Now you write the letter to him.
Wait, dont write with him in mind. Because if your customer is middle aged and carries a beer belly, he really doesnt exist. Write to the person your customer likes to be.
So write to the rugged, still young, making-the-girls-blush strapping young man who will benefit from your product. Write to the man who will without a moments notice realize that he is who your product is meant for. Write to the inner self and the outer self is pleased.
Getting your customer to be pleased with you is but the first step to making a sale.
And when you write to the man of his dreams, your customer will naturally, almost without noticing get your message and do what you ask him to do.