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