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