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