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