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