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