Please try to learn as much as possible about the Japanese culture. Don't just learn about anime, video games, and cosplay, but also about the food, history, lifestyle, relationships, etc. You might not care about some of this stuff, but trust me it will help. Why am I telling you these? Well some people that I new who came back after a trip to Japan, where so shock about the Japanese culture: The only knowledge they had about Japan was anime and cosplaying. This is a good website that I found about Japanese culture:
JREF - Japanese Culture Try to look for more places.