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