http://www.wikihow.com/Review-Using-Flash-Cards

1. Buy or make some cards. Make sure that they are approximately A6 size (half of an A5 piece of paper). Don't try to save money by getting paper - you can see through it, which allows you to unwittingly cheat. It must be lightweight card.
   
2. Write the keyword on the card. On one side of the card, write a very brief cue, key word or phrase, or possible exam question. For example "Solar system planets (in order of closest to sun)".
3. Write the answer on the other side. On the other side, write "Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune".
4. Make up several - or dozens - of such cards. You could color code them for different subjects - for example, have all blue cards for biology, and pink cards for physics.
5. Increase the complexity for essay exams. If you are reviewing for an essay-based exam, make the information on the back side of the cards more complex, so that you can see the word (for example, "Romeo") and be able to recall several points showing his love for Juliet, several points showing the complexity of his character, advantages and disadvantages of Shakespeare's portrayal of him, what the moral is, etc.
6. Test yourself. When you have made multiple cards, it's time to test yourself. Here's how you do it:
   
   

   • Pick up the first card and read the key words / phrase;
   • Try to recall as much of the information as you can;
   • Flip over the card and see if you got the answer(s) right;
   • If you're happy you got the information right, put that card on the 'right' pile. If you got the information wrong or incomplete, put it on the 'wrong' pile;

7. Do this for all the cards. When you've gone through all the cards, go to the 'wrong' pile, and repeat the process. Keep going through the 'wrong' pile until you get the information right, and there are no cards left in the 'wrong' pile.
8. Complete the process. Then go through the whole lot again for good measure.