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