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