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