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