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