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