What not to do on LinkedIn and why.

Best practices on LinkedIn are abundant, and so is the no-no list.
Here are 
some things to consider if you want to be successful on this great business networking platform.
1. Don't ask for recommendations.From people who don't know you, that is. Why would you expect someone without first hand knowledge of your expertise to say something great about you? I've gotten many requests like this and it always surprises me, and I never do it. Even worse: when it's sent out as a mass email...not cool.
2. You don't give back.
Great networking is based on giving, not receiving. Endorse another person's skills and you not only give them a virtual pat on the back, you may also help them show up in search results. Personally, I won't endorse anyone I don't feel comfortable endorsing, it's not genuine.

3. You've forgotten where you are.
LinkedIn is not Facebook. LinkedIn is a social networking site for professionals, so always present yourself in a professional manner. Show off your vacation and party pics someplace else. When you want to leave comments, share material, etc., always assume a potential employer, employee, customer, vendor is going to read it.
4. Don't be a salesperson in your groups.
Groups can be a great networking tool to grow your sphere of influence if you're engaged in the right way. DO NOT join a group if you're just going to promote your products or services, instead share useful information others in the group will find informative. The object is to build your reputation as a industry leader, and to develop useful relationships through communication.