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