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