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