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