Read, read, read

Read something you enjoy reading, the more you enjoy it, the more you will read and the more you read, the more vocabulary you will learn. It doesn’t matter if you are reading a signpost on the street or harry potter, you can learn English anywhere and everywhere.

Review, review, review

If you don't review, you'll forget. It is often boring to review, but it's absolutely essential to retain and consolidate vocabulary learnt. There's no point learning new words, in fact it would be a waste of time if you can't even remember the words you have learnt

Use and English English dictionary

It may be difficult at first but it will have far-reaching effects, as every time you learn a new word you will be reviewing old vocabulary. These days learner dictionaries only use around 2.000 of the most common words found in the English language. Such a vocabulary base should already be developed by the stage a student gets to high school. A translator may have short-term benefits but will only slow you down in the long run.

Use it or lose it

Always try to use new words in conversation or writing as this is the best way to remember a word. The more you use it, the easier it will be to recall next time you wish to use it.

Practice paraphrasing

As a non-native speaker, it doesn't matter how many words you learn, there'll always be a time when you don't know the word for something you wish to express. This'll be even more likely when you are in a test and you are feeling nervous, tired and maybe even scared. Therefore, its important that you have the ability to paraphrase. Open up any book or even a dictionary and see if you can describe a word using other words—you may use a synonym, parallel expression or even a sentence to describe your meaning. Even native speaker use this technique as everyone's mind goes blank from time to time.

Students most commonly use an incorrect word form. That is, they use a noun when they should use a verb or they use an adjective when they should use an adverb. When you learn a new word also find out that part of speech is and what the other word forms are.