Think about how you receive information best. Do you enjoy getting information that is theoretical, allowing you to process it and find meaning yourself? Or do you prefer information to be sensory, allowing you to learn procedures and look at facts? Perhaps you fit midway on the scale. Thinking about this will help you identify your personal learning style.
Consider areas where you remember information easily. Is it when the information is visual or when it is verbal? If you prefer visual information, then making a "mind map" of a subject or pinning your notes to the wall may improve your learning. If you prefer verbal information, read your notes out loud and record them. This way you will learn by reading them out loud and by listening to them.
Think about how you prefer to learn. Do you prefer to learn by doing or by thinking? If you prefer to touch objects, manipulate them and see how they work, then you are an "active" learner. Your learning style should involve as much tactile work as possible to help you remember information. If you prefer to think, you are a "reflective" learner, and you like to process information. Problem solving, such as crosswords and sudoku are a way you can strengthen your reflective brain.
Consider how you like to have information presented to you. If you like events to be described in a linear pattern, with ordered information, you are a "sequential" learner. Making a list of events or formula to remember will be most suited to your learning style. If you like information to be varied, and like avoiding lists, then you are a "global" learner. Take a piece of paper and write the event you are studying in the center. Around this, write the events which caused it and other important information. This will help you see the big picture and learn it as a whole.