Leave a few spaces blank as you move from one point to the next so that you can fill in additional points later if necessary. Do not try to take down everything the lecturer says. Spend more time listening and taking down the main points. If you are writing as fast as you can, you cannot be as discriminating a listener. Listen for cues to important points, transitions from one point to the next, repetition of points for emphasis, enumeration of a series of points, etc.
Many lecturers attempt to present a few major points and several minor points in a lecture.
The rest is explanatory material and examples. Try to see the main points and do not get lost in a barrage of minor points which seem unrelated to each other. The relationship is there if you listen for it. Take 5 minutes after class and summarize your notes. Develop a 1 page note summary that will remind you of everything you need to know.