Try keeping yourself always excited. Exposing yourself to top-level science will help you achieving this. Scientific American, National Geographics, Discovery Channel, Nature podcast, Science podcast, reading
books, attending academic meetings, talking with your friends over science, youtube, there are many ways to enjoy science and all of these will activate your brain.
Sometimes people (friends, supervisors, etc.) are unsympathetic with your scientific idea, but, don't hesitate to make mistakes and follow your own curiosity. Here you can read my experiences [Sorry it's written in Japanese].
The Campbell's Biology is one of the best text books for undergraduates to study biology. If you are reading the book, or will be reading the book, try finding questions or problems that are not
well-written in the text, because that is the way how you can train yourself as a scientist :)
Other Books: Read as many books as you can. Chemistry, Physics, Cognitive science, Computer Science, etc. Especially, History of Science will help you understand how scientists were often trapped in comon sense at each era.
The Lady Tasting Tea The Theory That Would Not Die
Get prepared for getting connected with scientists from all over the world. Yes, spend much time on learning English. Foreign students, don't hesitate to join us. I also have experiences of living abroad (Canada, Unted States), and I'm collaborate with researchers from various countries, including UK, USA, China, Taiwan, Denmark and so on. I'm also proud to tell you that Tokyo has been ranked as the safest city in this world, and the city of 24-7. What's University of Tokyo like? Watch the movie bellow. Admission policy for international students can be found here. It's very competitive, however, if you have good TOEFL, GRE and GPA scores, you have very high chance of getting it through! Schorlarship info. Please contact me if you are interested in joining our group:
7-3-1 Bunkyo-ku, Hongo 3cho-me, Tokyo, Japan
University of Tokyo, School of Science, Bld.2