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