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