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