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