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)(11,21,24,35,23,16,29,32)(12,25,27,36,28,17,30,34)(22,31,39,40,38,37,26,33)(1,2,5,3,6,8,4,7)(9,11)(10,16,18,21)(12,26)(13,29)(14,24)(15,23)(17,33,25,40)(19,35,20,32)(22,27)(28,39)(30,38)(31,36,37,34)(1,3,4,2,6,7,5,8)(9,12)(10,17)(11,22,23,38)(13,27)(14,30)(15,28)(16,31,21,37)(18,25)(19,34)(20,36)(24,26,29,39)(32,33,35,40)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.