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