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