Slurp Away
Yeah, you heard me. Slurp your noodles as much as you want. It shows that you are enjoying the meal. It is not considered rude as it is in many Western countries. In Japan, it is the opposite, and it is a cool aspect of their culture. And you get it, as we are sure you have been hungry and could not control your slurping.
If you do not do this, one might assume that the food is not good. At that rate, you run the risk of offending someone. You would not want that, now would you? Cannot imagine that would make for a good time with your host. So, when in Rome, in this case, Japan, slurp your nooooooooodles.