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