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