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