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