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