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