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