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