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