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