One vertex per element, one color per generator, with an edge from x to x·s.
(1,2)(3,4)(9,10,17,29,12,26,32,35,15,13,14,20,16,19,27,31)(11,21,39,37,33,23,30,18,25,40,24,36,22,38,34,28)(5,6)(7,8)(9,11,15,25)(10,18,13,28)(12,22,16,33)(14,30,17,34)(19,36,26,37)(20,38,29,23)(21,31,40,35)(24,27,39,32)(2,4)(6,8)(9,12,15,16)(10,19,13,26)(11,22,25,33)(14,27,17,32)(18,36,28,37)(20,35,29,31)(21,23,40,38)(24,30,39,34)(2,4)(9,13,15,10)(11,23,25,38)(12,26,16,19)(14,31,17,35)(18,30,28,34)(20,32,29,27)(21,22,40,33)(24,36,39,37)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.