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