"I have to study more."
How many times do you hear yourself saying that? How much studying do you actually do during the academic year?
Instead of studying, think about practice. Why? First of all, most people say that they feel that they should study.... but they actually don't do anything at all. Maybe they buy some books or maybe they have lists of vocabulary, but I'll tell you from experience - 90% of students don't even go that far.
Can you imagine what would happen if Alberto Contador wanted to win the Tour de France, but never got on his bicycle? Or if Cristiano Ronaldo wanted to win the World Cup for Portugal, but never put his shoes on? If you say that you want to study, but you don't do anything, all you do is guarantee that you will fail.
Here's an easier idea: Don't study - practice. Use your English every way you can. Listen to music. Write a journal. Watch short videos on YouTube. After all, you're learning English so that you can use it in the real world. The best way to use it in real situations is to practice in controlled situations, and to make it as diverse as possible.
If you think this advice is ridiculous, read this article from The New York Times: http://tinyurl.com/353qvzo.
Remember: You are the boss of your learning. Teachers are there to help you, but they cannot do your work for you.