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