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