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