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