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