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