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