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