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