In addition to michchick98ís text formatting tutorial, Iíve always found the following one by Weird Harold to be helpful in addressing some of the conversion issues from MS Word to a version that can be dropped directly into the submission box and not need additional work by the site editors.
Yes, it does require a somewhat higher level of understanding and comfort with MS Word, HTML, text editing, and file manipulation. And one would be correct in stating that the PREVIEW feature on the Lit submission page gives you a more direct and simpler way to do this, but I like having my manuscript 100% proofed and ready when I drop it into the submission box for preview. I guess Iím always wary of accidentally submitting the story before Iíve cleaned up the errors.
One thing Weird Harold didnít mention is the need to strip out his <html> Ö </html> coding (before and after your content) that enables you to see the mock-up of your storyís text in a browser. I forgot to do this one time and got the story kicked back to me for having unauthorized HTML code in my submission.