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