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