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