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