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