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