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