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