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