Hi,
The best notes would be the ones you write yourself. In business studies, for every topic there are several points and sub topics. It becomes tedious to keep all those points in your mind. But you can easily learn the most important and basic points and they can be used in several other topics. Also for notes after understanding a point write in short about everything you learnt in that topic. This will help in retaining the thing easily. Also while writing an answer try to explain as much as you can by making diagrams and explaining everything in points.