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