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