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