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