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