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