Reasons why using proper grammar will benefit you:
1. You appear more intelligent.
2. You can clearly express your thoughts, ideas, and opinions.
3. People are more likely to read your post.

Some short tutorials (compliments of Wikipedia) regarding some important parts of proper written communication.

Grammar - http://en.wikipedia.org/wiki/English_grammar
English grammar is a body of rules specifying how meanings are created in English. There are many accounts of the grammar, which tend to fall into two groups: the descriptivist, which describe the patterns through which meanings are typically created in functional speech and writing; and the prescriptivist, which set out pre-existing rules as to how meanings are created (see prescription and description).

Common mistakes related to grammar - http://hubpages.com/tag/grammar

Capitalization - http://en.wikipedia.org/wiki/Capitalization
For any word written in a language whose alphabet has distinct cases (such as the Latin, Greek, or Cyrillic alphabets), capitalization (or capitalisation) is the writing of a word with its first letter as a majuscule (upper case letter) and the remaining letters in minuscules (lower case letters). This is distinct from all caps and small caps, where a word is written entirely in uppercase.

Capitalized words may also be said to be in title case, since traditionally most words in titles of books, films, etc. are capitalized. In Unicode, a few letters have a separate title case form, where the Unicode character for the first letter of a capitalized word differs depending on whether the whole word is in upper case or just the initial letter (see Croatian and polytonic Greek below).

http://en.wikipedia.org/wiki/I...tions - some common guidelines for capitalization as it relates to written communication on the internet.

Punctuation - http://en.wikipedia.org/wiki/Punctuation
Punctuation is the act and the effect of punctuating, i.e., using punctuation marks.[1]

Punctuation marks are symbols that correspond to neither phonemes (sounds) of a language nor to lexemes (words and phrases), but which serve to indicate the structure and organization of writing, as well as intonation and pauses to be observed when reading it aloud. See orthography.

The rules of punctuation vary with language, location, register, and time, and are constantly evolving. Certain aspects of punctuation are stylistic, and thus the author's choice. A separate consideration should be reserved to tachygraphic language forms such as those used in chats and telephonic short messages. An English language bibliography may be found at the end of this article.

Paragraph - http://en.wikipedia.org/wiki/Paragraph
A paragraph is a self-contained unit of a discourse in a written text dealing with a particular point or idea, or the words of a speaker. The start of a paragraph is indicated by beginning on a new line and ending without running to the next passage. Sometimes the first line is indented, and sometimes it is indented without beginning a new line. At various times the beginning of a paragraph has been indicated by the pilcrow mark:¶.

Spelling - http://en.wikipedia.org/wiki/Spelling
Proper spelling is the writing of a word or words with all necessary letters and diacritics present in an accepted, conventional order. It is one of the elements of orthography and a prescriptive element of language. As a means of transcribing the sounds of language into alphabetic letters, spelling, however officially sanctioned, often offers but a rough and inconsistent approximation.

Whereas uniformity in the spelling of words is one of the features of a standard language in modern times, and official languages usually prescribe standard spelling, minority languages and regional languages often lack this trait. Furthermore, it is a relatively recent development in various major languages in national contexts, linked to the compiling of dictionaries, the founding of national academies, and other institutions of language maintenance, including compulsory mass education.

Learning proper spelling by rote is a traditional element of elementary education. In the US, the ubiquity of the phonics method of teaching reading, which emphasizes the importance of "sounding out" spelling in learning to read, also puts a premium on the prescriptive learning of spelling. For these reasons, divergence from standard spelling is often perceived as an index of stupidity, illiteracy, or lower class standing. The intelligence of Dan Quayle, for instance, was repeatedly disparaged for correcting a student's spelling of "potato" as "potatoe" at an elementary school spelling bee in Trenton, New Jersey on June 15, 1992[1]. In fact, "potatoe" is a variant, though long obsolete, historical spelling.

The opposite view was held when spelling began to be standardized, and was voiced by President Andrew Jackson who stated "It's a damn poor mind that can only think of one way to spell a word."

In countries such as the US and UK without official spelling policies, many vestigial and foreign spelling conventions work simultaneously. In countries where there is a national language maintenance policy, such as the Netherlands and Germany, reforms were driven to make spelling a better index of pronunciation. Spelling often evolves for simple reasons of alphabetic thrift, as when "catalogue" becomes "catalog."

Divergent spelling is also a popular advertising technique, used to attract attention or to render a trademark "suggestive" rather than "merely descriptive." The pastry chains Dunkin' Donuts and Krispy Kreme, for example, employ nonstandard spellings. The same technique is also popular among recording artists.

Since traditional language teaching methods emphasize written language over spoken language, a second-language speaker may have a better spelling ability than a native speaker despite having a poorer command of the language.

The International Phonetic Alphabet (IPA) aims to provide a medium of alphabetic characters to transcribe all sounds in all languages.

A couple notes on the easiest ways to ensure you are spelling correctly...
1. use the (ABC Check) Spell check button just above the text box entry portion of the forum thread post page.
2. Use Firefox 2.0 as your primary browser. It includes a built in active spelling correction tool for any time you are typing on a page hosted within the browser. - http://www.mozilla.com/product...en-US