Tips and Tricks for Better Letters: Following the proper formatting is only the first part of writing a letter that gets action. The content of a poorly formatted letter is unlikely to be read _ in one study of HR personnel, more than 80% said they’d throw out a resume if there were only one or two errors in the cover letter _ but even a well_formed letter is unlikely to be acted on unless the content is powerful and engaging. Once you have their attention, you need to create interest in whatever you’re offering. Promise to solve their problems _ with a great product, with your services, with a partnership, with whatever it is you’re writing about.
When you know the recipient’s name, sign it “Sincerely yours” or just “Sincerely”, or in the US “Yours truly” is acceptable. Don’t try anything more cutesy or friendly unless a) you know the recipient quite well and are certain you can be informal without seeming disrespectful, or b) you have a “trademark” letter ending that’s part of your public persona (and the talent and popularity to pull it off). Signature and printed name: Signing your name is a minimal assurance that you stand behind what was written.