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