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