Using your Dictionary flip it open to any page you want. Scroll down and stop at the first word that is unfamiliar to you. Write down the word, it's pronunciation, and its meaning. Write down the context if necessary. You can often get the gist of it with the example sentence.
Practice spelling the word on a separate sheet of paper. Write out your own example sentences. Two or three should be fine.
Repeat steps 1 and 2 until you have selected 3 to 5 new words.
Take your first sheet of paper(with just the words and meanings on them) and stick it in your purse, wallet, checkbook or any other place your sure to see it daily.
During the next week make a point of using your new words two or three times a day when you speak to others. This is an excellent way to memorize the words and integrate them into your natural speech patterns.
Make sure you know the definitions well, there is a very high probability that you will have to explain them to someone else.