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