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