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)(11,23)(12,28)(13,33)(14,21)(15,22)(16,20)(17,25)(18,31)(19,24)(26,37)(27,36)(29,40)(30,38)(32,35)(34,39) involution — undirected(9,11,14,26,15,27,16,25)(10,17,21,23,22,37,20,36)(12,29,31,34,32,24,30,13)(18,19,35,33,38,40,28,39)(2,5)(6,8)(9,12,15,32)(10,18)(11,24,27,29)(13,25,34,26)(14,31,16,30)(17,19)(20,28)(21,35)(22,38)(23,33)(36,39)(37,40)(1,3,4,7)(2,6,5,8)(9,13,14,29,15,34,16,24)(10,19,20,39,22,40,21,33)(11,12,26,31,27,32,25,30)(17,35,36,18,37,28,23,38)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.