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