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