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