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