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