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