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