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)(11,15)(12,16)(13,17)(14,18)(19,22)(20,23)(21,24)(25,26)(27,34)(28,31)(29,37)(30,33)(32,38)(35,39)(36,40) involution — undirected(2,5)(6,7)(9,10,14,18)(11,15,16,12)(13,17,21,24)(19,22,23,20)(25,27,30,28)(26,31,33,34)(29,35,38,36)(32,39,37,40)(1,2)(3,6)(4,5)(7,8)(11,16)(12,15)(13,21)(17,24)(25,26,30,33)(27,31,28,34)(29,37,38,32)(35,40,36,39)(1,3)(2,6)(4,8)(5,7)(9,11)(10,15)(12,18)(13,19)(14,16)(17,22)(20,24)(21,23)(25,26)(27,31)(28,34)(29,32)(30,33)(35,39)(36,40)(37,38) involution — undirected(9,12,14,15)(10,16,18,11)(13,20,21,22)(17,23,24,19)(25,28,30,27)(26,31,33,34)(29,36,38,35)(32,39,37,40)(9,13)(10,17)(11,19)(12,20)(14,21)(15,22)(16,23)(18,24)(25,29)(26,32)(27,35)(28,36)(30,38)(31,39)(33,37)(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.