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