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