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