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