The Union's booklet Author and Literary Agent contains a list of questions to ask your agent and should help you to reach an agreement. Be sure you have a letter of agreement or contract with the agent outlining the terms of your arrangement. It should be free of typographical errors. The title should appear on the top left hand corner of each page. Do not submit an entire manuscript to a publisher unless they so request.
Publishers prefer receiving a detailed outline with one or two sample chapters.
It is not uncommon for publishers to take three months or more to respond to your submission. If it is unsolicited, they are not obliged to respond. If a publisher is interested in your work, they will contact you. In your covering letter, state that it is a multiple submission. You do not have to indicate the names of the other publishers to whom you have submitted the manuscript.