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