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