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