There are 1001 factors that go into all sorts of different hair typs and how your will lock.
Most people find that the 4th month is the messiest. And a little while after that, they start to come together much more readily. Like Call said, mature locks take an average of a full year to mature. But around 8 months, they tend to look much more rope-like. But don't be surprised if they still don't. Or if they do earlier. There's no sure-fire way to predict it. Beanies tend to constrict movement and delay progress. Tams work much better at creating knots, but require more separating. A good salt soak before you wash helps a lot, too