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