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