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