If you are an affiliate, it is always advisable to write your own presale letter instead of using the standard one supplied by the company you are going to promote. This for three important reasons:
If a 3rd party describes the benefits of a product or service, even people don't know you, they will tend to believe this version more rather than the direct product/service owner.
Try not to reveal too much about the product/service in your presale letter, as by doing so you increase the curiosity of the reader to want to know more about what you are describing.
You have more control over the product you are promoting especially if you are building your own list. By doing so, you can easily follow-up the prospects with the aim to sell them other stuff, but also you'll be able to track the click through rate of the sales page you are using.
The general rule is that you should use the following format, which is based on my personal experience and that has always been perfectly working for me:
1) Tell a story A presale letter usually starts with the classic Feel-Felt-Found method which goes something like this… A) I know how you FEEL, B) In your position I FELT the same, C) Then I FOUND the following solution...
2) Give the proof and sell the dream To achieve a more powerful impact from your presale letter, you need to end it with these two things: A) The proof is usually given by a testimonial either in writing or even better through a video. B) The dream instead can be sold by showing pictures or a video of yourself on holiday in an exotic or expensive location.
3) Call to action If you are intent in building your own list, you have to make sure that your prospects will be able to access/view your product only after they have left you their email address through a capture page.
In case you are not building your own list, just supply them the (affiliate) link where they have to click and that takes them directly to the page you want them to see. Even better if you supply them with a shortened affiliate link, you can do this by using a free service available from a website such as: https://bitly.com
In case you don't have time to write a pre-sale letter at all, here is what you can do:
Write a powerful title or headline that stirs curiosity and sells the dream.
Show some proof of earnings.
Throw in some testimonials, with their pictures if possible.
Never forget to end your announcement asking for a “Call to action” such as: Get your report now!, Gain you FREE access now! Limited time only – Act now!, etc.
I believe the above can really make the difference between a weak marketing communication and a powerful one with the intent to sell your product/service.