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