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)(11,17)(12,21)(13,16)(14,22)(15,19)(18,23)(20,24)(25,26)(27,30)(28,31)(29,32)(33,40)(34,38)(35,37)(36,39)(1,3,5,4)(2,6,8,7)(9,11,13,19)(10,15,16,17)(12,18,22,24)(14,23,21,20)(25,27,28,34)(26,30,31,38)(29,33,36,35)(32,40,39,37)(1,3,5,4)(2,7,8,6)(9,12,21,10,13,22,14,16)(11,18,23,17,19,24,20,15)(26,31)(27,33)(29,36)(30,37)(34,35)(38,40)(1,4,5,3)(2,7,8,6)(10,16)(12,22)(15,17)(18,24)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.