Of course, you should be familiar with the Official Forum Rules if you choose to post anywhere. When posting in Casual Magic, however, please keep the following things in mind:
Normal Offenses: Spam: We appreciate constructive conversations and encourage you to participate. Please make sure your posts contribute to the threads before you click that button! If you are bumping your thread in order to bring attention to changes you have made in the OP, please list those changes in your update lest we view it as spam.
"Bumping": We understand that it can be frustrating if people don't comment on or respond to your threads quickly. Please be patient and avoid bumping your threads. Doing so may be considered spam.
Linking to Offsite Deck Lists: Links to deck lists are not allowed unless the link offers relevant on-topic content (like an article or discussion); you must post your deck list directly in your thread. If you need help figuring out how to use [deck] tags, please see this post. Linking to deck lists elsewhere without providing a list in the thread as well will be considered spam.
Multi Posting: MTGSalvation offers the use of an Edit Button for changing a post and a Multi-Quote Button to respond to several posts at once. We strongly encourage use of these features as opposed to multi posting. We reserve the right to merge multi posts from the same user. Excessive multi- or double-posting may be considered spam.
'Read This' Prefix: The 'Read This' prefix is considered Mod Text and may only be applied to threads by moderators or with moderator consent.
A matter of manners (these are just friendly reminders! ;)):
If you want your deck to be legal in an official format, please say so in your introductory post.
Use card- and deck-tags. It's much easier to talk about cards, when there are links to the oracle wording.
Before you post a decklist, check the Primers sticky or the specific subforum for it, as some decklists posted may benefit from them. Such decks may be given some time in the main forum to allow for development. However, if said decks do not develop beyond the "typical" type, they will be merged with the appropriate Primer.
Necroing: Please don't post in old threads unless you have a very important update to make. Traffic is already high enough and we don't need people to bump their decks constantly to the front page. If you aren't sure if your updates are significant enough to bump your old thread, please contact a forum moderator or post the question on our helpdesks.
We appreciate your cooperation. Welcome, and have fun!