What is the best way to learn vocabulary?

There is no 'best' way to learn vocabulary - different methods work for different people. However, simply looking up a word once isn't good enough, for you will soon forget it. One great way of learning new terms is to use them - try writing five sentences, in which you use the new word in different way each time. Online resources are really useful, too. Quizlet really helped me to learn new words (I'm currently making some Quizlets for my tutees) and you can use the app on your phone, so it's great for when you have a few spare minutes on the way to school, for example. Obviously, reading in the foreign language is really useful, too, and it will help you to gain a better understanding of the grammatical structures of the language - your subconscious mind will do the hard work for you!