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