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