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