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