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