The guidelines are a chance for you to crawl into the editors' heads and learn what they want. Not only that, but they often tell you exactly what editors want to see in e-mailed submissions. Read the guidelines to find out. Editors have different requirements and you can't satisfy every one of them in one e-mail. Format your submission properly.
Nothing turns a reader off of a story faster than running across an illegible section of text.
It takes a little extra work to format a manuscript properly but the eyesore editor will thank you. I've outlined the entire procedure here which will lead you step by step from word processing format to finished product. Include your contact information. Just as with snail mail submissions, you need to include your name and postal address in e-submissions. Editors need this information for contracts, payments and their records.