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