Complex sentence: Bolte was shrewd enough to see that the Liberals needed a new leader and a new image for the 1970s, and in August 1972 he resigned, apparently with no regrets, and arranged for Rupert Hamer, a Melbourne-based progressive Liberal, to succeed him.
Split into simpler sentences: Bolte was shrewd enough to see that the Liberals needed a new leader and a new image for the 1970s and in August 1972 he resigned, apparently with no regrets. He arranged for Rupert Hamer, a Melbourne-based progressive Liberal, to succeed him.