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