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