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