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