I like to use alot of diagrams and detailed drawings to explain concepts that may not have been illustrated previously. Things like flowcharts and graphs I find can be especially useful for biology along with notes that have been simplified so they can be understood easier. I find that if you enjoy the subject you are studying and make it more fun to learn about it encourages you to study more frequently. Using active revision techniques like regular quizzes or flashcards that I can help create will assist you with memorising important concepts.