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