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