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