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