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