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