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)(17,22)(18,21)(19,20)(23,24)(25,26,30,33)(27,29,35,31)(28,32,36,39)(34,37,40,38)(2,5)(6,7)(10,14)(15,21)(16,19)(22,23)(28,36)(32,39)(34,40)(37,38) involution — undirected(1,2)(3,6)(4,5)(7,8)(25,27,30,35)(26,31,33,29)(28,34,36,40)(32,38,39,37)(1,3,4,8)(2,6,5,7)(9,11,13,18)(10,15,14,21)(12,17,20,24)(16,22,19,23)(25,27)(26,29)(28,34)(30,35)(31,33)(32,37)(36,40)(38,39)(9,10)(11,15)(12,19)(13,14)(16,20)(17,23)(18,21)(22,24)(25,28,30,36)(26,32,33,39)(27,34,35,40)(29,37,31,38)(9,12)(10,16)(11,17)(13,20)(14,19)(15,22)(18,24)(21,23)(25,29)(26,27)(28,37)(30,31)(32,34)(33,35)(36,38)(39,40) 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.