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