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