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