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