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