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