Have you wondered why people spend money buying things?
From my point of view they expect to get back something more valuable than the amount of money they spend.

By consequence, they won't buy from you until they will see an extra value in your offer. How can you add this extra value in your sales letter ?
Let's see:

1. Explain the reason why youre making this offer.
For example you're doing it because you are tired of seeing people scammed on the Internet and want to provide them with solid info they can use for immediate profit.

2. Explain why your product is important.
Any customer only care about how he can personally benefit by using your product/service. So, try to explain in details how your product fits his needs and how his life will be improved. Show your potential customers their problem; agitate it by telling them how troublesome it is, then offer your product as the solution.

3. Explain the product value.
Prospects won't buy from you unless they know exactly the value of what you're offering them. Then, tell them what they want to know about your product and why it's worth the price.

4. Explain that they can start using its benefits very fast If they want your product, they want it on the spot. The faster you can deliver your product or service the more sales you'll get. An overnight delivery is very efficient, the customers are eager to pay some extra money for that.

5. Explain that there is no risk involved.
An unconditional, money back guarantee will produce the most sales because it completely eliminates all of the customer's risk. This nothing to risk guarantee shows your confidence in your own product. Then offer the most liberal guarantee you can afford and state it clear in all details.