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