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