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