[tmbsundar]

1 - While learning some subject learn surrounding concepts or related facts as well. For example, if you are learning Calculus - learn the historical context, infinitesimal approach. If you are preparing for an exam and your text book gives one method and a specific topic, try learning related additional concepts and additional methods. This will help in not forgetting the core concept of technique. A close approximation scenario(not entirely true - but gives you an idea): you learn one forget one, learn four and retain two.

2 - Spaced Repetition - people have covered already.

3 - Active Recall - https://en.wikipedia.org/wiki/Active_recall

4 - Active Learning - https://en.wikipedia.org/wiki/Active_learning

Edit: Paragraph alignment