Clean up code on an html newsletter document

I have produced a newsletter, in html format, using some email marketing software. But when I said it to myself as a test, part of the message is missing. I would like either 1. my document corrected, so it works and adding in a few more graphics to make it look more professional or 2. to create another document I can use instead This is a very small document, 4 images, about a page of text, a link and some simple graphics.