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