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