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