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