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