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