Complex sentence: He drew inspiration for his performance as the older Nicky from Peter Flannery himself, basing aspects of his characterisation on Flannery's personality and even wearing some of the writer's own colourful shirts.
Split into simpler sentences: He drew inspiration for his performance as the older Nicky from Peter Flannery himself, basing aspects of his characterisation on Flannery's personality. He even wore some of the writer's own colourful shirts.