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