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