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