There is a tendency to think that the often arbitrary rules of letter writing don’t really matter, that as long as your recipient can work out what you’re saying, that’s good enough. This shows a great deal of disrespect for your recipient, though, and for your own ideas. It suggests that a) your reader’s time isn’t valuable enough for you to write clearly and efficiently, and b) that you don’t particularly care about the content of your letter.
Signatures if You're Emailing. If you are sending your cover letter or inquiry letter by email, end with a polite sign_off followed by your full name. You do not need to sign a cover letter that is being sent electronically. Write out your full name in the same font as the rest of the letter, and there's no need for italics or a handwriting font. The formatting here is very similar to an uploaded cover letter. However, emails do not contain a header with your phone number or other contact information. It's a good idea to include these details in your closing paragraph or after your typed signature. That makes it easy for the employer or networking contact to get in touch with you.