I suggest you check out the website www.memrise.com I don't use it myself, but I've heard many people say it's very helpful for drilling vocabulary. You might find it useful. Good luck with your studies!

Correction: I would like to know the best way to memorize, (memorize in American English), vocabulary words. Answer: I always tell my students that the best way to memorize vocabulary is to use the words in everyday conversation. That is hard to do if you do not speak English with other people every day. Another good way to study/memorize vocabulary is to use notecards. Write the English word on one side and the definition on the other side in English if you know it, or in your native language if you do not know all the English for it. Study these cards when you have free time, like when you are waiting for the bus.