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