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