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)(18,22)(19,20)(25,26,29,30)(27,31,34,38)(28,35,37,32)(33,40,36,39)(1,2,5,4)(3,6,7,8)(9,10,14,12)(11,15,16,13)(18,22)(23,24)(26,30)(31,38)(32,35)(39,40)(9,11,14,16)(10,15,12,13)(17,18,21,22)(19,23,20,24)(25,26)(27,31)(28,32)(29,30)(33,39)(34,38)(35,37)(36,40)(1,3)(2,6)(4,8)(5,7)(9,12,14,10)(11,13,16,15)(17,19,21,20)(18,23,22,24)(25,27,29,34)(26,31,30,38)(28,36,37,33)(32,40,35,39)(1,4,5,2)(3,8,7,6)(9,13)(10,11)(12,16)(14,15)(17,20,21,19)(18,24,22,23)(25,28,29,37)(26,32,30,35)(27,33,34,36)(31,39,38,40)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.