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