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