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