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