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