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