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