Be an active listener. Avoid distractions such as cellphones -- turn them off and put them away. Commit to being engaged for the full lecture. Don't rely on tape recorders, which can become a detrimental crutch, giving you the sense that you can zone out during the lectures and listen later. Taking notes while someone is giving a lecture reinforces your learning, because you're actively engaging with the information: listening carefully for key points and jotting down those points.
When you're going to hear a lecture on something -- whether it's your professor leading a literary discussion or a realtor giving a presentation -- know before you go. Familiarizing yourself with the material beforehand helps you identify key points so you can concentrate more closely on the fine details that support those main ideas. Read the material before class or do some light research on the topic. Create an outline of the key points or a list of vocabulary or concepts relevant to the topic. Listen out for these buzz words. Pay attention to cues from the speaker: long pauses and posed questions.
Even if you're able to jot down everything that's important, it's not going to be helpful to you as a disorganized, illegible mess. Learn how to format your notes in a clean, organized fashion. Leave a line space between each main idea. Use a highlighter to make central ideas more prominent and easy to find. The Cornell University Note Taking System recommends dividing your page into 3 sections: left margin, body of the page and bottom margin. List topics, questions and talking points in the left margin. Use the body of the page to jot down details, and in the bottom margin, write a concise summary of what was covered.
Review your notes after taking them -- the sooner the better. Ideally you'll want to review them the day after taking them and again before the next lecture or discussion as a refresher. Take notes on your notes, which might seem like strange advice, but this practice reinforces your memory and comprehension of the material. Transfer your notes to a Word document. If you're more visual, include visual aids -- such as charts, graphs, photos -- to your notes.