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