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