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