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