make notes don't take notes. draw diagrams and connect words together keeping in mind what their definitions mean. To build a puzzle you don't start in the middle. You usually want to get the border done because those pieces got something in common and there are less of them. There are lot less concepts than there are biology facts. By getting the border done to your puzzle and getting the concepts down, it will be easier to see how the details/facts fit into your puzzle. I like analogies 🙂