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