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