Bald patches and lack of connective regions is something that happens to some men, and is usually genetic. I know this because I am also currently growing a beard, and have a bald spot under my chin, a mustache that refuses to grow, and no possibility of a goatee because the connective region between the mustache and chin is nonexistent.
I've heard that lack of testosterone could cause these problems (the 20 odds of today have less testosterone than their fathers, mostly because of red meat having estrogen based hormone in it), so potentially talk to a doctor about that possibility, if you care enough.
The basic strategy to growing a beard is to let it go, without interference, for six weeks-two months. Take stock of it there. Trim it to what you want, or let it keep going if you want something big. I'm going to see if mine will get any longer, and attempt a braid if I can. Right now it's a bushy chin curtain, which I also like.