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