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