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)(11,22)(12,27)(13,21)(14,20)(15,18)(16,23)(17,25)(19,24)(26,33)(28,37)(29,40)(30,32)(31,34)(35,38)(36,39) involution — undirected(2,5)(6,8)(9,11,13,25,16,26,14,15)(10,17,20,22,23,18,21,33)(12,24,28,38,30,39,29,31)(19,32,34,37,36,27,35,40)(1,3,4,7)(2,6,5,8)(9,11,13,25,16,26,14,15)(10,18,20,33,23,17,21,22)(12,24,28,38,30,39,29,31)(19,27,34,40,36,32,35,37)(9,12)(10,19)(11,24)(13,28)(14,29)(15,31)(16,30)(17,32)(18,27)(20,34)(21,35)(22,37)(23,36)(25,38)(26,39)(33,40) 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.