It is just a matter of patience. Just let it grow and dont be tempted to trim. A little jojoba oil in the morning and a couple of blasts with a hairdryer on cool setting should train it over time. One mistake not to fall in to, (I did), is not to cut it in two tight under the chin as you need the mass behind to push it out and down.

Being bearded isnt always easy, but it is always worth it