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