Applying images and sounds
1.- When you learn some word, you should have an idea of an image of this one, and when you need remember this word only you refresh your mind and revive this image with the word.
2.- You can try to make a semantic map. This works as a union of ideas. Only, you put the words and some that you can link for understand better. Or in another context, you can make a semantic map with words look alike.
3.- Another form of to remember a new idiom is using special words, for this one is:
identifying the words same other that you can remember so you will create a visual image of this new word.