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