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