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