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