Step 1. Context
First, you need to establish context. Explain who you are and why you are talking to the reader. Context comes down to the reason why your audience is being exposed to your message.
Step 2. Attention
Grab the reader’s attention with the headline and/or the design.
Step 3. Desire
Make the audience want something badly enough to keep on reading.
Step 4. The Gap
Establishing the gap means explaining the difference between what will happen if the reader does nothing and what will happen if the reader takes advantage of your product/service. Describe what happens when nothing changes using examples and case studies to highlight the consequences of not taking action.
Step 5. Solution
Transition quickly into your solution. Keep the explanation of how your solution works on a strictly need-to-know basis so you don't provide reasons to disagree with you.
Step 6. Call to action
Explicitly ask the audience to take one action, and only one.
This is not exactly a step. You establish credibility all the way through your messaging. Show the reader that you understand their pain and that you know what you are talking about (demonstrate social proof, demonstrate your expertise, apply risk-reversal).