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