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