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