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