Improve vocabulary by making words personally relevant
By nature, your mind tends to block out information that is meaningless to you personally. Conversely, information that has personal relevance to you will be retained in your memory for a longer time. If you want to improve vocabulary, it is therefore very important to attach relevance to new words so you can recall them easily.
Use words in a personal context
If there's a new word that you want to learn, use it in a phrase that is significant to you personally. For instance, you want to remember the word "incorrigible," which is defined as "one who is beyond correction."
You can remember it better, and in the process, improve vocabulary, by thinking about your incorrigible nephew who misbehaves so much it makes his sister cry in frustration. Then use the word in conversation, like when you call your mother. You can tell her that Dave might be an incorrigible brat but he couldn't be an angel if he wanted to be.
Make your own definition
When you look up a word in the dictionary, make sure you understand the given meaning then word it in your own way, adding a personal touch. You can then take the word "incorrigible" and define it as "my stubborn nephew who refuses to listen to his mother's lectures."