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