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