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