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