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