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