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