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