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