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