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