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