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