A student, Mohammad Ali Mohammad, asked me the following question:
1. Try to use the word immediately by creating your own sentence. Say it aloud. Don't just read the word from a book or a dictionary. Saying the words aloud is very powerful for memorization.
2. Make a word list and study the same words every few days until they are imprinted in your mind.
3. Google the word to see how it's used in different contexts.
4. Have a dictionary. (not just an online dictionary, but an actual book) When you learn the meaning of a new word, underline it. Then, once in a while scan your dictionary looking for the underlined words and check to see if you still remember the meaning. It's a nice way to see your own progress. I used this method with learning French. It was so exciting to look through my dictionary and to see how many words I didn't know just six months before. It encouraged me to keep learning and to become fluent.
Do you readers have any other suggestions?