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