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