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