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