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