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