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