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