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