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