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