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