What I tell students time after time, increasing your vocabulary has to be the most important aspect of English language development. Whether you are true beginner or an advanced level learner, you need the tools necessary to be able to communicate effectively as well as understand who you are listening to.
What we recommend our students is having a notebook or file on your computer where you can constantly add new vocabulary words in an organized and efficient manner. You only need 10 to 15 minutes a day to review new and old vocabulary words. Reviewing is essential in turning short term knowledge (new vocabulary) into long term memory.