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