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