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