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