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