Dig dip. Dig dense. That's the only way to study. Studying for only exams is not the way..... study to be a good engineer, study to understand, study to get the facts. This is how things will be easy when you get into the industry. So remember this when you studying your subjects.
Best way for me was when I took pen and paper. I remember those topics very clearly which I studied with pen and paper. And there was another topics that I remember very clearly and those were the one which I had discussion with my friends.
So study with pen and paper, jot down what you read, make diagrams, visual maps and freely discuss what you are learning with your friends, state what you have understood and how the topic you learnt applies to your and our life. This simple exercises will cement the topic in your mind, bond it in your knowledge, so give it a try!
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