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