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