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