You can only post a new message or reply to an existing message from a board index (new message) or from within a message thread (replies). As clearly stated on  ASI Rules - http://amsellingit.com/market/general-discussion/asi-rules-please-read/, you are not allowed to post any abusive, obscene, vulgar, slanderous, hateful, threatening, sexually-oriented or any other material that may violate any applicable laws.

Posting your product for sale is easy on ASI. All you need to do is post the product(Item) name, item store URL and the item description.  If you have a related products for sale, please post on an existing thread, there is no need for creating a new thread to advertise(announce) your product.

Before posting your product or message you can:
- attach your Signature
- edit your Signature
- preview your message to check how it will look before it is posted for everyone to see.

You can click on 'Additional Options...' right below the text area to see additional features for you post.

Happy posting.