Here's an easy-to-follow, 7-step sales letter template for professional or business service providers.

1.   Get attention
Getting the attention is the primary importance of any direct marketing piece.   The goal is to engage the reader enough to get them to read the rest of the letter.  The key to doing that is to make it interesting enough, but also it must be believable.

Here are several ways you can grab the reader's attention in a sales letter...

• Promise a benefit ("Reduce  your marketing costs in half in just 90 days"
• Ask an intriguing question:  ("What do 90% of all small businesses overlook when saving on income taxes?"
• Make an offer ("Reply now and get a 10-page free report to help you get more customers").

2.  Identify the problem your reader has

After you get the reader's attention, you immediately want to identify the relevant problem the reader has that your service can solve.  Generally, the problems for most businesses fall under these general categories:

• how to save money (reduce costs)
• how to make more money (increase revenues, increase profits)
• how to improve operations, increase productivity

You'll want to state the problem in a way that the reader can recognize it.  In a essence, you must help the reader discover (or rediscover) a real problem, pain or predicament they have, so that they will be thinking about when you introduce your service as the solution to it in the next step of the letter.

3.  Position your service as the solution to the problem.

Now that the reader is thinking about or feeling the pain of the problem you just identified, you now want briefly position that your service is the solution to that problem.

4.  Prove that your service is the solution to the problem.

To prove the case, there are three basic items you should try to include in the letter to reinforce your position. 

• mention the primary benefits of your service, and how they can measurably solve the problem the reader faces.
• mention any "social proof" that you have that your service provides the benefits you are promising.  This can be done by mentioning testimonials of real clients, or describing "mini case studies" or success stories of previous client projects.  It's important to note results here, not just just make claims.
• what credentials do you have?  In support of the other two items above, you can weave information about your experience, training, technology you use, professionalism, etc.   While these credentials aren't usually effective on their own, they do help support other types of proof in your letter.

5.  Give them an offer

All sales letters need an offer. 

Are you offering a free seminar?  A free special report?   A complimentary assessment or one-hour consultation?   Or perhaps a low-cost introductory sampling of your service?

What is it that you are offering to get them to reply to you? 

Offers can be spiced up by adding two elements:  scarcity and/or exclusivity.  Doing so you state that the offer is good only for a limited time, or for a limited number of people. 

Examples:

"Our seminar only has 30 seats available." 
"We are only offering the report until Dec. 31" 

6.  Make sure it has a guarantee.

A guarantee helps "reverse" any risk the reader might be worried about if he or she replies to your offer.

If you're offer is free, you might try something like "The consultation is absolutely free.  There is no obligation to purchase the service."

Other guarantees include:

"If you aren't satisfied with our work, you don't pay."
"Everything is done in 30 days or less, or your money back."

7. Tell them what to do

This is the "call to action."   Many sales letters forget this part, even though it seems obvious to include it.

You must tell them exactly what you want them to do to get the offer -- and make it easy for them to respond.

Some examples:

"Fill out the postage-paid reply card and drop in in the mail today"
"Go to .www.ourwebsite.com and enter your email address on the top of our home page."
"Call us at 1-800-XXX-XXXX and our trained representatives will get the report out to right away."

It's also a good idea to provide multiple ways for readers to respond (such as mail, telephone, fax, email, etc.).   The more way they can respond, the higher potential for response.