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