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