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