How do I learn more words?

A. Use good techniques.

See: What is the best way to learn new words?

B. Learn the rules of morphology (word building).

You can enlarge your vocabulary very easily by learning how to form new words from the ones you already know e.g. educational or re-educate from education. The Academic Word list consists of 570 headwords, but if you add in all the different forms of these headwords, the final number is around 3,000 words. Since a different word form will have a related meaning to the original word, it is easier to learn and remember than a completely new word. Once you have learnt how words are formed in English, you may find that you can easily guess the meanings of new words or even can predict what the form of a new word will be, based on one you already know.

Some useful sites for helping you to learn about morphological rules or how to form words are:

C. Study little and often.

See: How long should I spend each day on learning new words?