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