Building on What You Know
You've got a good foundation; the next step is to build on what you've learned. One of the best ways to start out is to take a chapter theme from this book, or any other materials that you have, and expand on that theme. Let's use Chapter 15's topic of shopping as an example of what you can do with any theme you select. After reviewing the vocabulary that you've learned, use your dictionary to expand your list. Go through your closet and dresser and list every item of clothing you own. Practice describing each item in as much detail as possible. Say what you like about it, remind yourself of how you acquired it, how much it cost, etc. Do the same thing for every type of item you might shop for and you will expand your vocabulary enormously!
You can never learn too many words! Make a game of expanding your vocabulary in different categories that you find interesting. Set goals to learn a certain number of words each week.
Practice Vocabulary and Grammar in Context
Using the theme you have reviewed as a context, practice conversational interactions in as many ways as you can think of by writing out dialogs, role-playing with a friend, or simply talking to yourself. Little by little, make your practice more complex. For example, ask the salesperson more questions; shop for more items; practice talking about problems with an item you want to buy or have bought and are returning. For themes that you are less expert with, use your imagination to create likely scenarios. Repetition is the key to internalizing vocabulary and becoming comfortable with multiple possibilities in any given situation. Let's take a minute to summarize:
Review what you know.
Expand on what you know thematically.
Use a dictionary and other resources to increase your vocabulary thematically.
Invent thematic scenarios to practice vocabulary and grammar points in context. Practice saying the same thing in a variety of ways.
When you feel like you have exhausted the possibilities for one theme, move on to another one your find particularly interesting. You will never run out of topics to pursue and, with the Internet, it's very easy to access information about them in Spanish.
Learn about Your Hobbies
Another way to spice up your learning is to explore some of your hobbies in the context of the Hispanic world. Learn all the vocabulary related to one of your hobbies, and find out where and how it is practiced in Spain and Latin America. Practice talking about your hobby in Spanish. Say how long you have been interested in it, how you got started, and why you like it. Follow your favorite sports online; learn about athletes and entertainers that you are interested in. Investigate the history, art, music, literature of a country that you might like to visit.