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