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