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