Many people want to know the “magic formula” is for writing web site and ad copy that sells.
If you're one of those folks who would like to know that formula, I have some disappointing news: there isn't one.
“But Ray,” I hear you say, “Haven't you yourself taught several different copywriting ‘formulas'?”
They are not “magic” and they don't work universally.
What a formula can do is give you a basic structure on which to hang your “argument” (your logic for why someone should buy your stuff); what the formula cannot do is somehow magically compel people to buy something they don't really want or need.
What a formula can't do is teach you the fears and aspirations of your readers, so that your persuasion power comes from the point of intersection between your audience's needs/desires and your product's features/benefits.
Only you, as an empathetic writer, can do that.