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