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