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