You can't be successful in business without having good negotiation skills.
You will have to negotiate with customers, employees, vendors...
Some people are good negotiators by nature and they even enjoy this experience.
But many others have to learn how to do it.
One of the most important rules of negotiation is patience. Those who can be patient all the way - will succeed at the end.
The ability to listen is very important too. You should be able not to hear but listen. The more you can listen to the other party, the better position you will be in.
It is also nesessary to be fair and honest during negotiations. Even simple expressions and body movements can make a big difference.
Open mind and compromise are other useful qualities.
And, of course, before negotiations start, you should get prepared yourself with all nesessary information - it will help you to present your arguments in a convincing manner.