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