Complex sentence: Afterward, Hines would spend most of his time engaged in secret missions in his beloved Kentucky, often by himself as he was dressed in civilian clothes and did not want any extra attention, as he did not want to be executed as a spy.
Split into simpler sentences: Afterward, Hines would spend most of his time engaged in secret missions in his beloved Kentucky. He was often by himself because he was dressed in civilian clothes and did not want any extra attention, as he did not want to be executed as a spy.