Top ten self explanatory things not to do when promoting your brand in social media.
1. Don't make spelling or grammatical errors.
2. Don't cut & paste from platform to platform
3. Don't fail to test links.
4. Don't paste the same thing more than once every three hours.
5. Don't use, "text speak".
6. Don't fail to use tags that involve others, @ on Twitter, Names on Facebook.
7. Don't use your brand properties to have strictly personal discussions.
8. Don't post blindly, study what works & why.
9. Don't "try" to be clever.
10. Don't be LAZY which is what one through nine mean.
To summarize, take your time, edit, be honest, trust your instincts, study what works. Businesses don't "post" on social media they execute well thought out tactically constructed strategies with a specific goal in mind.