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