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