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