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