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