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