Complex sentence: On 6 January 1953, having gave up his job a month before, Christie sold most of his furniture--even his bed, and slept on an old mattress for the next 11 weeks.
Split into simpler sentences: On 6 January 1953, having gave up his job a month before, Christie sold most of his furniture, including his bed. He slept on an old mattress for the next 11 weeks.