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