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