Font Size: The traditional font size for a professional letter is 12. The font should be Times New Roman or Arial. However, if you are using letterhead, the letterhead may be in different font size and style. Font Style: There is no need to use different styles within a professional letter. Use a uniform font (book print font such as Times New Roman or Arial) and avoid underlining, italicizing, or bolding. However, if you are using letterhead, the letterhead may be in a different font style.
Then you arouse their desire by explaining how you can do this — for instance, by showing how successful you’ve been in other positions, or by explaining the specialized training you have relevant to the job. Avoid jargon here — explain clearly and concisely the benefits of the solution you offer. When I worked in marketing, I learned an important lesson: nobody buys anything based on features (and “buy” is used in its loosest possible sense, like you “buy” an idea). You have to explain exactly how those features will benefit the potential buyer.