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