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