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