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