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