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