3. Ellipsis:
The ellipsis is a series of three -- and ONLY THREE -- full stops used to mark missing words, an uncertain pause, or an abrupt interruption. Avoid the temptation to use six or seven dots -- it looks amateurish. For example, we write:

Niles: But Miss Fine`s age is only ...
Fran: Young! Miss Fine`s age is only young!

4. Excessive punctuation:
Only one exclamation mark or question mark should be used at a time. Consider the following over-punctuated examples:

Buy now!!!
Great bargains!!!!!!!!!! Excessive punctuation looks too much like hysteria and detracts from your credibility. Avoid it.
5. Headings:
For long works, establish a clear hierarchy of headings. Microsoft Word`s heading styles are great for this. (They also allow you to automatically create a table of contents.)
6. Hyphenating prefixes:
Most prefixes don`t need a hyphen; i.e. we write "coexist", not "co-exist". There are exceptions, though. The prefixes "self-" and "ex-" are almost always hyphenated.
7. Numbers:
Numbers of ten or less are normally written as words.
8. Quotation marks:
Users of American English should use double quotes (" "). Users of British English should choose either single quotes (` `) or double quotes and stick with them for the whole document. Incidentally, British English usage is increasingly moving towards single quotes.
9. Spaces:
Modern style is to use a single space at the end of a sentence, not two. Also, most punctuation marks (e.g. commas, full stops, question marks) are not preceded by a space.
10.Tables:
Set table text one or two points smaller than the main body text and in a sans-serif font such as Arial or Verdana. Avoid vertical lines as they tend to add unnecessary clutter.
Armed with these simple guidelines, your business writing should be well received every time. Good luck!