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