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