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