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