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