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