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