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