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