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