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