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