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