One vertex per element, one color per generator, with an edge from x to x·s.
(1,2)(3,4)(9,10,15,22,13,20,30,34,14,21,16,23,17,24,31,40)(11,25,27,37,29,35,32,19,12,18,28,36,26,39,33,38)(2,4)(5,6)(7,8)(9,11,15,27,13,29,30,32,14,12,16,28,17,26,31,33)(10,18,22,36,20,39,34,38,21,25,23,37,24,35,40,19)(6,8)(9,12,14,11)(10,19,21,38)(13,29,17,26)(15,32,16,33)(18,34,25,40)(20,37,24,36)(22,35,23,39)(27,31,28,30)(2,4)(9,13,14,17)(10,20,21,24)(11,26,12,29)(15,30,16,31)(18,35,25,39)(19,37,38,36)(22,34,23,40)(27,33,28,32)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.