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