We have been asked this question by a lot of students - how do I build my vocabulary? The honest answer is that there is no easy way. You can memorize a thousand flash cards without it making any material impact on your vocabulary. To have a good vocabulary you need to be introduced to words in a context. The more vivid the context the more likely it is that you will remember the word. Hence, adjectives should remind you of a person, nouns of real life examples etc. The best way to do this would be through books. Reading good quality books will have the natural side effect of improving your vocabulary.
However this may not be a good preparation plan for CAT if the exam is two months away. In that case try to solve as many vocabulary related questions as you can. Questions, especially incorrectly solved ones, have higher recall value as compared to ordinary vocabulary building methods like flash cards.