Complex sentence: She was popular and outgoing; although she planned to pursue a Master's degree, she taught English for a year in Japan starting in October 2006 at the Koiwa, Tokyo branch of Novathen Japan's largest private English conversation school.
Split into simpler sentences: She was popular and outgoing; although she planned to pursue a Master's degree, she opted to teach English for a year in Japan. She moved to Japan in October 2006 to teach English at the Koiwa branch of Nova in Tokyo, which was Japan's largest private English conversation school.