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