Write the words down on flash cards. You can buy blank flash cards online at Officedepot.com. I have included a link below in the resources section of the page. Write the word or phrase on one side, and the meaning or translation on the other. It doesn't matter if they are French words, Spanish words, Japanese words, or long phrases. This way you won't have to cover the other word up if they are next to each other in a book. This especially helps if you are trying to memorize dictionary words as they are always printed so tiny.
Once you have all of your vocab cads together, practice saying the word out loud as you look it. This stimulates both visual and audio senses at the same time. So whatever type of learner you are this will work. Keep going through the stack until you can recite all words and definitions instantly. The key is practice.
Now reverse the process and read the cards backwards. You should be able to know the word when you see the definition and the definition when you see the word. When it comes to taking a test it's always better to be safe than sorry. I have used these techniques to memorize foreign language vocab words throughout high school. I even used it to memorize GRE words about a week ago.