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