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