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