Front side only. Your name, address, telephone and e-mail on the first page. Your name and the story title in the header of all subsequent pages. Page numbers in the upper right corner. Leave the right margins ragged.
Staple pages together, or use binders.
Send them loose, in the correct page order. No italics or fancy fonts. Trying to impress an editor with your computer skills is like trying to impress Davis Copperfield with the old disappearing quarter trick. No graphics of any kind. Get thee to a book store and buy thyself a current writers market guide.