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