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