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)(19,22)(20,21)(23,24)(25,26)(27,29)(28,35)(30,32)(31,33)(34,37)(36,39)(38,40)(1,2)(3,5)(4,6)(7,8)(9,11)(10,14)(12,19)(13,18)(15,17)(16,22)(20,23)(21,24)(25,27)(26,28)(29,33)(30,34)(31,35)(32,36)(37,40)(38,39) involution — undirected(11,18)(14,15)(19,24)(22,23)(25,28,31,29)(26,27,33,35)(30,37,38,36)(32,39,40,34)(1,3,4,7)(2,5,6,8)(9,10)(11,14)(12,20)(13,17)(15,18)(16,21)(19,23)(22,24)(25,29,31,28)(26,27,33,35)(30,36,38,37)(32,39,40,34)(9,11)(10,15)(12,19)(13,18)(14,17)(16,23)(20,22)(21,24)(25,27)(26,28)(29,33)(30,34)(31,35)(32,36)(37,40)(38,39) involution — undirected(9,12)(10,16)(11,19)(13,21)(14,22)(15,23)(17,20)(18,24)(25,30)(26,32)(27,34)(28,36)(29,37)(31,38)(33,40)(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.