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