In a business setting, there are two main reasons why our listening skills might need improvement: either a lack of focus on what a person is saying, or because we are, ourselves, talking. So the quickest and easiest ways of improving listening are to reverse those two habits.
Instead of making statements, ask questions. Practice withholding your own opinions and feedback and letting the person give you a complete answer.
Listening also becomes easier if you are looking directly at the person who is speaking. In part because you are literally focused on the person, and partly because you also see their lips moving as they speak, which reinforces communication and understanding.